--- category: Apps description: Building and shipping Products on the Polkadot platform, from identity setup and local development through to deployment and discovery. page_count: 76 token_estimate: 9589 updated: '2026-06-25T12:38:13.291384+00:00' --- ## Account Management Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/account-management.md TrUAPI Account Management method group for resolving sub-accounts, reading account state, and using @parity/product-sdk-signer to get Product accounts. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## App Development Reference https://docs.polkadot.com/reference/apps.md Technical reference for building Polkadot Products, including Hosts, TrUAPI between Host and Product, and the on-chain infrastructure they consume. ### Sections - Introduction `#introduction` - Architecture `#architecture` - Hosts `#hosts` - Protocol `#protocol` - Infrastructure `#infrastructure` - Skills `#skills` - Where to Go Next `#where-to-go-next` --- ## Apps https://docs.polkadot.com/apps.md Build Polkadot Products, sandboxed apps that run inside the Polkadot Hosts, addressed by .dot domain names, and signed by the user's phone. ### Sections - Get the Polkadot App `#get-the-polkadot-app` - Then Pick Your Path `#then-pick-your-path` - What Is a Polkadot Product? `#what-is-a-polkadot-product` - Why Build a Polkadot Product? `#why-build-a-polkadot-product` --- ## Build https://docs.polkadot.com/apps/build.md Build Polkadot Product capabilities with product-sdk packages for signing, on-chain reads, decentralized storage, off-chain pub/sub, and local persistence. ### Sections - Set Up Your Project `#set-up-your-project` - Capabilities `#capabilities` - The product-sdk Packages `#the-product-sdk-packages` - Umbrella or Individual Packages `#umbrella-or-individual-packages` --- ## Build a Shared Todo App https://docs.polkadot.com/apps/tutorials/shared-todo-app.md Build a complete Polkadot Product end to end with a shared todo board that combines signing, local persistence, real-time pub/sub, and on-chain storage. ### Sections - Introduction `#introduction` - Prerequisites `#prerequisites` - Scaffold the Project `#scaffold-the-project` - Connect and Get an Identity `#connect-and-get-an-identity` - Keep State on the Device `#keep-state-on-the-device` - Share the Board in Real Time `#share-the-board-in-real-time` - Make the Board Durable `#make-the-board-durable` - Wire Up the Page `#wire-up-the-page` - Run It `#run-it` - Ship It `#ship-it` - Where to Go Next `#where-to-go-next` --- ## Bulletin Chain Authorization https://docs.polkadot.com/reference/apps/infrastructure/bulletin-chain/authorization.md How writes to the Bulletin Chain are gated — the explicit per-account authorization model, the transaction-and-byte quota, and the expiration lifecycle. ### Sections - Introduction `#introduction` - What an Authorization Records `#what-an-authorization-records` - What a Write Costs `#what-a-write-costs` - Expiration `#expiration` - Provisioning on TestNet `#provisioning-on-testnet` - Where to Go Next `#where-to-go-next` --- ## Bulletin Chain Reference https://docs.polkadot.com/reference/apps/infrastructure/bulletin-chain.md Reference for the Bulletin Chain — Polkadot's decentralized, content-addressed storage layer for Products, with authorization, chunked uploads, and renewal. ### Sections - Introduction `#introduction` - Architecture `#architecture` - When to Use Bulletin `#when-to-use-bulletin` - Where to Go Next `#where-to-go-next` --- ## Bulletin Chain Renewal https://docs.polkadot.com/reference/apps/infrastructure/bulletin-chain/renewal.md The retention lifecycle for data on the Bulletin Chain — default window, what happens at expiration, and the mechanics of renewing data before it falls off. ### Sections - Introduction `#introduction` - The Default Retention Window `#the-default-retention-window` - What Renewal Does `#what-renewal-does` - What Renewal Costs `#what-renewal-costs` - What Happens to Forgotten Data `#what-happens-to-forgotten-data` - Where to Go Next `#where-to-go-next` --- ## Chain Interaction Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/chain-interaction.md TrUAPI method group for reading chain state and subscribing to changes, behind @parity/product-sdk-chain-client and the typed PAPI API exposed per chain. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## Chat in the Polkadot App https://docs.polkadot.com/reference/apps/hosts/polkadot-app/chat.md Reference for Polkadot App Chat, room and bot registration, typed messages, custom rendering, and how it composes Statement Store with Bulletin Chain. ### Sections - Introduction `#introduction` - Room and Bot Registration `#room-and-bot-registration` - Message Types `#message-types` - Custom Message Rendering `#custom-message-rendering` - Message Queueing `#message-queueing` - Composition: Statement Store + Bulletin Chain `#composition-statement-store-bulletin-chain` - Where to Go Next `#where-to-go-next` --- ## Chat Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/chat.md TrUAPI method group for in-App chat, including room and bot registration, typed message publishing, and custom message rendering by subscription. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## Chunked Uploads on the Bulletin Chain https://docs.polkadot.com/reference/apps/infrastructure/bulletin-chain/chunked-upload.md How payloads larger than the per-transaction byte limit are uploaded as chunks under a DAG-PB manifest, transparently to the Product. ### Sections - Introduction `#introduction` - What Happens Internally `#what-happens-internally` - What This Costs `#what-this-costs` - What a Product Sees `#what-a-product-sees` - Where to Go Next `#where-to-go-next` --- ## Coinage in the Polkadot App https://docs.polkadot.com/reference/apps/hosts/polkadot-app/coinage.md Reference for Coinage, the Polkadot App's peer-to-peer payment flow with the privacy and personhood-gating properties of the pallet-coinage primitive. ### Sections - Introduction `#introduction` - Conceptual Model `#conceptual-model` - Where to Go Next `#where-to-go-next` --- ## Cross-Chain Bulletin Storage via People Chain https://docs.polkadot.com/reference/apps/infrastructure/bulletin-chain/cross-chain.md How a Bulletin Chain storage call initiated from the People Chain — where a Product's Proof of Personhood identity lives — reaches the Bulletin Chain via XCM. ### Sections - Introduction `#introduction` - The Flow `#the-flow` - When to Use the Cross-Chain Path `#when-to-use-the-cross-chain-path` - Where to Go Next `#where-to-go-next` --- ## Deploy Your App https://docs.polkadot.com/apps/deploy-your-app.md Deploy your Polkadot Product to the playground using the playground CLI — build, upload, and publish your app on-chain and register a .dot name. ### Sections - Introduction `#introduction` - Prerequisites `#prerequisites` - Build Your App Bundle `#build-your-app-bundle` - Deploy Your App `#deploy-your-app` - Open Your App `#open-your-app` --- ## dotNS Architecture https://docs.polkadot.com/reference/apps/infrastructure/dotns/architecture.md The cooperating contracts on Asset Hub that back the dotNS registry — name records, ownership, content references, and PopRules enforcement. ### Sections - Introduction `#introduction` - Conceptual Responsibilities `#conceptual-responsibilities` - Where to Go Next `#where-to-go-next` --- ## dotNS CLI Reference https://docs.polkadot.com/reference/apps/infrastructure/dotns/cli.md Reference for @parity/dotns-cli — the command-line tool for managing .dot name registrations, contenthash updates, transfers, and renewals. ### Sections - Introduction `#introduction` - Command Families `#command-families` - Installing and Authenticating `#installing-and-authenticating` - Command Surface `#command-surface` - Where to Go Next `#where-to-go-next` --- ## dotNS Reference https://docs.polkadot.com/reference/apps/infrastructure/dotns.md Reference for dotNS — the .dot name system on Asset Hub that resolves Product names to published bundles, with PopRules pricing and contract architecture. ### Sections - Introduction `#introduction` - Where to Go Next `#where-to-go-next` --- ## dotNS TestNet Contracts https://docs.polkadot.com/reference/apps/infrastructure/dotns/testnet-contracts.md Current Paseo TestNet contract addresses for the dotNS registry — registry core, registration and pricing, and lifecycle contract families. ### Sections - Introduction `#introduction` - Contract Address Table `#contract-address-table` - How to Use These Addresses `#how-to-use-these-addresses` - Where to Go Next `#where-to-go-next` --- ## Entropy Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/entropy.md TrUAPI method group for deriving deterministic per-Product entropy from the user's root key, suitable for seeding Product-local key material. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## Get TestNet Tokens https://docs.polkadot.com/apps/get-started/get-testnet-tokens.md Claim TestNet tokens from the Polkadot Faucet and unlock per-service allowances for Bulletin Chain, Statement Store, and dotNS. ### Sections - Prerequisites `#prerequisites` - Get Tokens `#get-tokens` - Service Allowances `#service-allowances` - Where to Go Next `#where-to-go-next` --- ## HOP Recipient Journey https://docs.polkadot.com/reference/apps/infrastructure/hop/recipient.md The receiving side of a HOP transfer — observing the incoming hop on the destination chain, validating the proof, and settling the resulting state. ### Sections - Introduction `#introduction` - The Flow at a Glance `#the-flow-at-a-glance` - What the Recipient's Product Sees `#what-the-recipients-product-sees` - Where to Go Next `#where-to-go-next` --- ## HOP Reference https://docs.polkadot.com/reference/apps/infrastructure/hop.md Reference for HOP — Polkadot's cross-chain hop protocol that moves assets and messages between chains, with current maturity-state caveats clearly flagged. ### Sections - Introduction `#introduction` - Where HOP Fits `#where-hop-fits` - Where to Go Next `#where-to-go-next` --- ## HOP Sender Journey https://docs.polkadot.com/reference/apps/infrastructure/hop/sender.md The sender side of a HOP transfer — dispatching a multi-hop send, tracking it as it routes through intermediate chains, and observing the final outcome. ### Sections - Introduction `#introduction` - The Flow at a Glance `#the-flow-at-a-glance` - What Can Go Wrong `#what-can-go-wrong` - Where to Go Next `#where-to-go-next` --- ## Host API on Polkadot Web https://docs.polkadot.com/reference/apps/hosts/polkadot-web/host-api.md Reference for the TrUAPI Host API surface exposed by Polkadot Web, including shared Desktop behavior and where browser-context behavior differs. ### Sections - Introduction `#introduction` - What Is the Same `#what-is-the-same` - Where Browser-Context Differs `#where-browser-context-differs` - Where to Go Next `#where-to-go-next` --- ## How HOP Works https://docs.polkadot.com/reference/apps/infrastructure/hop/how-it-works.md The HOP protocol's conceptual model — what a hop is, how multi-hop routing is constructed, and how the verifier model proves cross-chain correctness. ### Sections - Introduction `#introduction` - What a Single Hop Is `#what-a-single-hop-is` - How Multi-Hop Routing Is Constructed `#how-multi-hop-routing-is-constructed` - The Verifier Model `#the-verifier-model` - What a Product Sees `#what-a-product-sees` - Where to Go Next `#where-to-go-next` --- ## Install Polkadot Desktop and Pair https://docs.polkadot.com/apps/get-started.md Install Polkadot Desktop, pair it with the Polkadot App on your phone with a QR scan, and set up the foundation for local Polkadot Product development. ### Sections - Introduction `#introduction` - Prerequisites `#prerequisites` - Install Polkadot Desktop `#install-polkadot-desktop` - Pair Polkadot Desktop with the Polkadot App `#pair-polkadot-desktop-with-the-polkadot-app` - Where to Go Next `#where-to-go-next` --- ## Local Storage Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/local-storage.md TrUAPI Local Storage method group for per-Product, per-device key-value persistence, Host-managed namespaces, JSON helpers, and KvStore use. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## Name Transfers https://docs.polkadot.com/reference/apps/infrastructure/dotns/transfer.md Transferring ownership of a .dot name to another account — the flow, the validation rules, and what changes on the new owner's side. ### Sections - Introduction `#introduction` - What Changes on Transfer `#what-changes-on-transfer` - When the Tier Lock Matters `#when-the-tier-lock-matters` - What a Product Should Know `#what-a-product-should-know` - Where to Go Next `#where-to-go-next` --- ## On-Chain polkadot.com https://docs.polkadot.com/reference/apps/hosts/polkadot-web/onchain-polkadot-com.md Reference for the on-chain-published presence backing polkadot.com discovery, a Polkadot Product that indexes and points at other Polkadot Products. ### Sections - Introduction `#introduction` - Why an On-Chain Discovery Layer `#why-an-on-chain-discovery-layer` - Implications for a Product Developer `#implications-for-a-product-developer` - Where to Go Next `#where-to-go-next` --- ## pallet-coinage Reference https://docs.polkadot.com/reference/apps/infrastructure/pop/pallet-coinage.md The PoP pallet behind the Polkadot App's Coinage feature — personhood-aware peer-to-peer payments with privacy properties beyond a standard Balances transfer. ### Sections - Introduction `#introduction` - Conceptual Surface `#conceptual-surface` - Relationship to Coinage in the App `#relationship-to-coinage-in-the-app` - Pallet Surface `#pallet-surface` - Where to Go Next `#where-to-go-next` --- ## pallet-game Reference https://docs.polkadot.com/reference/apps/infrastructure/pop/pallet-game.md The PoP pallet for personhood-gated on-chain games and randomized selection — fair-draw mechanics that rely on Ring-VRF aliases for unique participation. ### Sections - Introduction `#introduction` - What the Pallet Guarantees `#what-the-pallet-guarantees` - What a Product Uses It For `#what-a-product-uses-it-for` - Where to Go Next `#where-to-go-next` --- ## pallet-identity Reference https://docs.polkadot.com/reference/apps/infrastructure/pop/pallet-identity.md The People Chain identity record associated with a PoP account — what it stores, how it relates to aliases, and how a Product reads from it. ### Sections - Introduction `#introduction` - What the Pallet Records `#what-the-pallet-records` - Identity vs. Aliases `#identity-vs-aliases` - When to Use From a Product `#when-to-use-from-a-product` - Where to Go Next `#where-to-go-next` --- ## pallet-people Reference https://docs.polkadot.com/reference/apps/infrastructure/pop/pallet-people.md The foundational Proof of Personhood pallet — personhood registration, ring membership, alias issuance, and the under_alias runtime origin. ### Sections - Introduction `#introduction` - Ring Membership `#ring-membership` - Alias Issuance `#alias-issuance` - `under_alias` Dispatch `#under_alias-dispatch` - Pallets That Depend on This One `#pallets-that-depend-on-this-one` - Where to Go Next `#where-to-go-next` --- ## pallet-score Reference https://docs.polkadot.com/reference/apps/infrastructure/pop/pallet-score.md The PoP pallet for personhood-anchored reputation and scoring — per-alias scores that accumulate while staying unlinkable to user accounts. ### Sections - Introduction `#introduction` - What the Pallet Records `#what-the-pallet-records` - Read and Write Paths `#read-and-write-paths` - Use Cases `#use-cases` - Where to Go Next `#where-to-go-next` --- ## pallet-ubc Reference https://docs.polkadot.com/reference/apps/infrastructure/pop/pallet-ubc.md The Universal Basic Capacity pallet — per-person on-chain capacity primitives, including the periodic fee-free transaction quota for verified persons. ### Sections - Introduction `#introduction` - What the Pallet Provides `#what-the-pallet-provides` - When a Product Reaches for UBC `#when-a-product-reaches-for-ubc` - Eligibility Constraints `#eligibility-constraints` - Where to Go Next `#where-to-go-next` --- ## Payment Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/payment.md TrUAPI method group for payment flows, including the standard Balances transfer surface and the Pocket peer-to-peer flow for Product payments. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## Permissions in Polkadot Desktop https://docs.polkadot.com/reference/apps/hosts/polkadot-desktop/permissions.md Reference for how Polkadot Desktop enforces sandbox permissions a Product declares, including capability types, manifest declaration, and denial UX. ### Sections - Introduction `#introduction` - Capability Types `#capability-types` - Declaring Permissions `#declaring-permissions` - Denial UX `#denial-ux` - Where to Go Next `#where-to-go-next` --- ## Permissions Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/permissions.md TrUAPI method group for declaring, querying, and gating on Product capabilities, including the ChainSubmit, ExternalRequest, and Microphone surfaces. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## Persist Data Locally https://docs.polkadot.com/apps/build/persist-data-locally.md Learn how to store and retrieve application data between sessions in a Polkadot Product using the @parity/product-sdk-local-storage package. ### Sections - Introduction `#introduction` - Prerequisites `#prerequisites` - Install the SDK `#install-the-sdk` - Initialize the Store `#initialize-the-store` - Store String Values `#store-string-values` - Store JSON Values `#store-json-values` - Remove Stored Values `#remove-stored-values` - Namespace Keys with Prefixes `#namespace-keys-with-prefixes` - Use React Hooks `#use-react-hooks` - Limitations `#limitations` - Where to Go Next `#where-to-go-next` --- ## Pocket Recipient in the Polkadot App https://docs.polkadot.com/reference/apps/hosts/polkadot-app/pocket.md Reference for how the Polkadot App receives a Pocket transfer initiated from Desktop, including the recipient-side flow for funds or assets. ### Sections - Introduction `#introduction` - Conceptual Model `#conceptual-model` - Where to Go Next `#where-to-go-next` --- ## Pocket Send Flow in Polkadot Desktop https://docs.polkadot.com/reference/apps/hosts/polkadot-desktop/pocket.md Reference for Pocket, Polkadot Desktop's peer-to-peer send flow with personhood-aware addressing, and how it pairs with the App-side recipient view. ### Sections - Introduction `#introduction` - Conceptual Model `#conceptual-model` - What the User Sees `#what-the-user-sees` - Where to Go Next `#where-to-go-next` --- ## Polkadot App Reference https://docs.polkadot.com/reference/apps/hosts/polkadot-app.md Reference for the Polkadot App, the mobile Host in the Triangle that holds the user's signing key, runs PoP, and approves every Product transaction. ### Sections - Introduction `#introduction` - How It Works `#how-it-works` - Where the App Fits in the SDK Surface `#where-the-app-fits-in-the-sdk-surface` - Where to Go Next `#where-to-go-next` --- ## Polkadot Desktop Reference https://docs.polkadot.com/reference/apps/hosts/polkadot-desktop.md Reference for Polkadot Desktop, the desktop Host that loads Products by .dot name, mediates signing to the App, and enforces sandbox permissions. ### Sections - Introduction `#introduction` - How It Works `#how-it-works` - Where Desktop Fits in the SDK Surface `#where-desktop-fits-in-the-sdk-surface` - Where to Go Next `#where-to-go-next` --- ## Polkadot Product Skills https://docs.polkadot.com/reference/apps/skills.md Reference for the product-sdk skills — modular instructions that teach an AI agent how to work effectively across the Polkadot Products stack. ### Sections - Introduction `#introduction` - Skills List `#skills-list` - How to Install `#how-to-install` - Updating `#updating` - Where to Go Next `#where-to-go-next` --- ## Polkadot Web Reference https://docs.polkadot.com/reference/apps/hosts/polkadot-web.md Reference for Polkadot Web (dot.li), the browser-based Host that loads Polkadot Products by their .dot name without requiring a desktop installation. ### Sections - Introduction `#introduction` - Architecture `#architecture` - Visiting and Shield States `#visiting-and-shield-states` - Host API on Web `#host-api-on-web` - On-Chain `polkadot.com` `#on-chain-polkadotcom` - Upload Journeys `#upload-journeys` - Where to Go Next `#where-to-go-next` --- ## PopRules and dotNS Pricing https://docs.polkadot.com/reference/apps/infrastructure/dotns/poprules-pricing.md The pricing ladder for .dot name registration — who can register what name length at what cost, organized by PoP tier and suffix shape. ### Sections - Introduction `#introduction` - The Two PoP Tiers `#the-two-pop-tiers` - The Pricing Ladder `#the-pricing-ladder` - Lite → Full Migration Reservation `#lite-full-migration-reservation` - Where to Go Next `#where-to-go-next` --- ## Preimage Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/preimage.md TrUAPI method group for submitting off-chain content that on-chain operations dereference by hash, with preimage and Statement Store distinction. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## Preimage Submission via Polkadot Desktop https://docs.polkadot.com/reference/apps/hosts/polkadot-desktop/preimage.md Reference for how Polkadot Desktop mediates preimage submission for Products, and the Statement vs Preimage distinction for off-chain content. ### Sections - Introduction `#introduction` - What the Preimage Surface Does `#what-the-preimage-surface-does` - Statement vs Preimage `#statement-vs-preimage` - Where to Go Next `#where-to-go-next` --- ## Proof of Personhood in the Polkadot App https://docs.polkadot.com/reference/apps/hosts/polkadot-app/pop.md Reference for how the Polkadot App runs Proof of Personhood, with biometric verification, Ring-VRF aliases on People Chain, and the PoP tier model. ### Sections - Introduction `#introduction` - Ring-VRF Aliases `#ring-vrf-aliases` - PoP Tiers: Full vs. Lite `#pop-tiers-full-vs-lite` - What This Unlocks for a Product `#what-this-unlocks-for-a-product` - Where to Go Next `#where-to-go-next` --- ## Proof of Personhood Reference https://docs.polkadot.com/reference/apps/infrastructure/pop.md Reference for Polkadot's Proof of Personhood infrastructure — Ring-VRF and aliases, plus per-pallet documentation for the pallets that gate logic on personhood. ### Sections - Introduction `#introduction` - The Mechanism `#the-mechanism` - The Pallets `#the-pallets` - Where to Go Next `#where-to-go-next` --- ## Publish and Subscribe to Off-Chain Data https://docs.polkadot.com/apps/build/pub-sub-off-chain-data.md Publish and subscribe to off-chain data from a Polkadot Product using the Statement Store. Filter by topic, publish statements, and use channels. ### Sections - Introduction `#introduction` - Prerequisites `#prerequisites` - Install the SDK `#install-the-sdk` - Set Up Your Statement Store Client `#set-up-your-statement-store-client` - Subscribe to Incoming Statements `#subscribe-to-incoming-statements` - Publish a Typed Statement `#publish-a-typed-statement` - Use a Channel for Last-Write-Wins State `#use-a-channel-for-last-write-wins-state` - Where to Go Next `#where-to-go-next` --- ## Quick Start with RevX https://docs.polkadot.com/apps/quick-start.md Generate and publish a Polkadot Product from the browser with RevX App Builder, then sign the final .dot deployment with the Polkadot App. ### Sections - Prerequisites `#prerequisites` - Open RevX `#open-revx` - Open App Builder `#open-app-builder` - Create a New App `#create-a-new-app` - Configure the Builder `#configure-the-builder` - Generate an App `#generate-an-app` - Inspect the Generated Code `#inspect-the-generated-code` - Publish to `.dot` `#publish-to-dot` - Where to Go Next `#where-to-go-next` --- ## Quick Start with the CLI https://docs.polkadot.com/apps/quick-start-cli.md Install playground-cli, pair it with the Polkadot App, build your Product, and deploy it to a live .dot name from the terminal. ### Sections - Prerequisites `#prerequisites` - Install the CLI `#install-the-cli` - Initialize `#initialize` - Build `#build` - Deploy `#deploy` - Where to Go Next `#where-to-go-next` --- ## Read On-Chain Data https://docs.polkadot.com/apps/build/read-chain-state.md Connect a Polkadot Product to one or more chains and read storage, constants, and account state using the @parity/product-sdk-chain-client package. ### Sections - Introduction `#introduction` - Prerequisites `#prerequisites` - Install the SDK `#install-the-sdk` - Connect to a Chain `#connect-to-a-chain` - Connect Using a Preset `#connect-using-a-preset` - Connect Using Custom Descriptors (BYOD) `#connect-using-custom-descriptors-byod` - Read Storage and Constants `#read-storage-and-constants` - Read Multiple Chains in Parallel `#read-multiple-chains-in-parallel` - Access the Raw PAPI Client `#access-the-raw-papi-client` - Detect Whether You Are Inside a Host `#detect-whether-you-are-inside-a-host` - Clean Up Connections `#clean-up-connections` - Limitations `#limitations` - Where to Go Next `#where-to-go-next` --- ## Ring-VRF and Aliases https://docs.polkadot.com/reference/apps/infrastructure/pop/ring-vrf-and-aliases.md How Polkadot's Proof of Personhood produces unlinkable per-Product aliases with Ring-VRF, and how under_alias lets pallets gate on aliases. ### Sections - Introduction `#introduction` - What PoP Produces `#what-pop-produces` - What an Alias Is `#what-an-alias-is` - The `under_alias` Runtime Origin `#the-under_alias-runtime-origin` - Cross-Product Aliases `#cross-product-aliases` - Where to Go Next `#where-to-go-next` --- ## Sandbox and Sub-Accounts in TrUAPI https://docs.polkadot.com/reference/apps/protocol/truapi/sandbox.md Why a Polkadot Product gets a per-domain sub-account, why the Host API is the only egress, and how permissions selectively relax that isolation. ### Sections - Introduction `#introduction` - Why Derived Sub-Accounts, Not Root Identity `#why-derived-sub-accounts-not-root-identity` - Why the Host API Is the Only Egress `#why-the-host-api-is-the-only-egress` - How Permissions Selectively Relax Isolation `#how-permissions-selectively-relax-isolation` - Where to Go Next `#where-to-go-next` --- ## Shield States in Polkadot Web https://docs.polkadot.com/reference/apps/hosts/polkadot-web/shield-states.md Reference for the shield-state UI in Polkadot Web, including how the Host surfaces the trust posture of the loaded Product and what each state means. ### Sections - Introduction `#introduction` - Conceptual Model `#conceptual-model` - Why Products Should Care `#why-products-should-care` - Where to Go Next `#where-to-go-next` --- ## Sign and Submit Transactions https://docs.polkadot.com/apps/build/sign-and-submit.md Derive product-scoped accounts and sign transactions from a Polkadot Product using the Product SDK, with all approvals routed to the Polkadot App. ### Sections - Introduction `#introduction` - Prerequisites `#prerequisites` - Install the SDK `#install-the-sdk` - How Product Accounts Work `#how-product-accounts-work` - Set Up Signer Manager `#set-up-signer-manager` - Connect to the Host `#connect-to-the-host` - Get a Product Account `#get-a-product-account` - Sign Arbitrary Bytes `#sign-arbitrary-bytes` - Sign and Submit a Transaction `#sign-and-submit-a-transaction` - Handle Signing Errors `#handle-signing-errors` - Test Without a Host `#test-without-a-host` - Limitations `#limitations` - Where to Go Next `#where-to-go-next` --- ## Sign In with Polkadot https://docs.polkadot.com/reference/apps/hosts/polkadot-app/sign-in.md Reference for Sign In with Polkadot, the Host-level authentication handshake between Polkadot Desktop or Polkadot Web and the paired Polkadot App. ### Sections - Introduction `#introduction` - How the Handshake Works `#how-the-handshake-works` - Where Sign In Differs from Per-Transaction Signing `#where-sign-in-differs-from-per-transaction-signing` - Where to Go Next `#where-to-go-next` --- ## Signing in Polkadot Desktop https://docs.polkadot.com/reference/apps/hosts/polkadot-desktop/signing.md Reference for how Polkadot Desktop mediates transaction signing, including the App signer, ChainSubmit permission, approval, timeout, and rejection. ### Sections - Introduction `#introduction` - The Three-Actor Model `#the-three-actor-model` - `ChainSubmit`: Ability to Request ≠ Auto-Sign `#chainsubmit-ability-to-request-auto-sign` - What the User Sees `#what-the-user-sees` - Asynchronous Approval and Timeouts `#asynchronous-approval-and-timeouts` - Where to Go Next `#where-to-go-next` --- ## Signing Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/signing.md TrUAPI method group for dispatching transactions through the Host to the paired Polkadot App for per-transaction approval, signing, and results. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Auto-Signing `#auto-signing` - Where to Go Next `#where-to-go-next` --- ## Statement Lifecycle https://docs.polkadot.com/reference/apps/infrastructure/statement-store/lifecycle.md How a Statement Store submission moves through validation, gossip propagation, TTL expiry, and eviction — and what each step guarantees. ### Sections - Introduction `#introduction` - The Five Steps `#the-five-steps` - What Each Step Guarantees `#what-each-step-guarantees` - On-Chain Trigger (Forthcoming) `#on-chain-trigger-forthcoming` - Where to Go Next `#where-to-go-next` --- ## Statement Store Allowance https://docs.polkadot.com/reference/apps/infrastructure/statement-store/allowance.md How per-account statement quota is enforced — max_count for live statements and max_size for total bytes — and why submissions are gated rather than fee-priced. ### Sections - Introduction `#introduction` - What an Allowance Records `#what-an-allowance-records` - How the Limits Interact `#how-the-limits-interact` - Per-Statement Size Limit `#per-statement-size-limit` - Provisioning on TestNet `#provisioning-on-testnet` - Where to Go Next `#where-to-go-next` --- ## Statement Store Channels https://docs.polkadot.com/reference/apps/infrastructure/statement-store/channels.md The last-write-wins primitive on top of statements — a channel field causes the pallet to replace older entries from the same account on the same channel. ### Sections - Introduction `#introduction` - When to Reach for Channels `#when-to-reach-for-channels` - Scope and Replacement Rules `#scope-and-replacement-rules` - The Channel-Store API `#the-channel-store-api` - Where to Go Next `#where-to-go-next` --- ## Statement Store Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/statement-store.md TrUAPI method group for publishing and subscribing to gossip-distributed signed statements on the People Chain through the Host and SDK client. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## Statement Store Reference https://docs.polkadot.com/reference/apps/infrastructure/statement-store.md Reference for the Statement Store — Polkadot's network-layer pub/sub primitive on the People Chain, with on-chain rules and off-chain payloads via gossip. ### Sections - Introduction `#introduction` - How a Statement Reaches Subscribers `#how-a-statement-reaches-subscribers` - Delivery Semantics `#delivery-semantics` - Where to Go Next `#where-to-go-next` --- ## Statement Store Subscriptions https://docs.polkadot.com/reference/apps/infrastructure/statement-store/subscriptions.md How a subscriber registers a topic filter against the People Chain node — primary topic, optional secondary topic, dedup behavior, and unsubscription. ### Sections - Introduction `#introduction` - How Topics Filter `#how-topics-filter` - What the Callback Receives `#what-the-callback-receives` - Subscription Lifecycle `#subscription-lifecycle` - Initial-State Behavior `#initial-state-behavior` - Where to Go Next `#where-to-go-next` --- ## Statement Store via Polkadot Desktop's Host API https://docs.polkadot.com/reference/apps/hosts/polkadot-desktop/statement-store.md Reference for how Polkadot Desktop mediates Statement Store access, including proof routing, account context, and Bulletin Chain composition pattern. ### Sections - Introduction `#introduction` - What Desktop Adds `#what-desktop-adds` - What Desktop Does Not Do `#what-desktop-does-not-do` - Composition with the Bulletin Chain `#composition-with-the-bulletin-chain` - Where to Go Next `#where-to-go-next` --- ## Store Data on Chain https://docs.polkadot.com/apps/build/store-data-on-chain.md Store and retrieve Bulletin Chain data from a Polkadot Product, Hello World, larger files, renewal, cross-chain via People Chain, preimage-authorized uploads. ### Sections - Introduction `#introduction` - Prerequisites `#prerequisites` - Install the SDK `#install-the-sdk` - Set Up Your Storage Client `#set-up-your-storage-client` - Store a Hello World `#store-a-hello-world` - Retrieve Your Data `#retrieve-your-data` - Store a Larger File `#store-a-larger-file` - Get Authorization `#get-authorization` - Renew Long-Lived Data `#renew-long-lived-data` - Cross-Chain Storage from People Chain `#cross-chain-storage-from-people-chain` - Submit a Preimage `#submit-a-preimage` - Storage Paths at a Glance `#storage-paths-at-a-glance` - Where to Go Next `#where-to-go-next` --- ## The .dot Name Mechanism https://docs.polkadot.com/reference/apps/infrastructure/dotns/name-mechanism.md How a .dot name resolves to a Polkadot Product — namehash derivation, contenthash to CID mapping, and the IPFS gateway and Bulletin Chain delivery path. ### Sections - Introduction `#introduction` - Layer 1: The Registry on Asset Hub `#layer-1-the-registry-on-asset-hub` - Layer 2: Namehash Derivation `#layer-2-namehash-derivation` - Layer 3: `contenthash` → CID `#layer-3-contenthash-cid` - Layer 4: Delivery (IPFS Gateway or Bulletin Peer-to-Peer) `#layer-4-delivery-ipfs-gateway-or-bulletin-peer-to-peer` - End-to-End Resolution `#end-to-end-resolution` - Where to Go Next `#where-to-go-next` --- ## TrUAPI Calls Method Group https://docs.polkadot.com/reference/apps/protocol/truapi/calls.md The lifecycle calls a Product uses to identify itself to its Host, the Host capability introduction, and the setup every TrUAPI group relies on. ### Sections - Introduction `#introduction` - Conceptual Contract `#conceptual-contract` - Where to Go Next `#where-to-go-next` --- ## TrUAPI Packages https://docs.polkadot.com/reference/apps/protocol/truapi/packages.md Which SDK package wraps which TrUAPI method group, and where the boundary between Product code and Host code lives in the package reference. ### Sections - Introduction `#introduction` - Package Map `#package-map` - The Boundary Between Product Code and Host Code `#the-boundary-between-product-code-and-host-code` - Where to Go Next `#where-to-go-next` --- ## TrUAPI Reference https://docs.polkadot.com/reference/apps/protocol/truapi.md TrUAPI is the protocol between Polkadot Hosts and the Products that run inside them, covering signing, chain interaction, storage, and messaging. ### Sections - Introduction `#introduction` - Two Audiences `#two-audiences` - The Eleven Method Groups `#the-eleven-method-groups` - High-Level Diagram `#high-level-diagram` - Where to Go Next `#where-to-go-next` --- ## TrUAPI Versioning https://docs.polkadot.com/reference/apps/protocol/truapi/versioning.md How TrUAPI versions evolve, what compatibility a Product can rely on across Host versions, and how to target a specific version range safely. ### Sections - Introduction `#introduction` - What a Version Number Identifies `#what-a-version-number-identifies` - What a Product Targets `#what-a-product-targets` - How the SDK Maps to Versions `#how-the-sdk-maps-to-versions` - Where to Go Next `#where-to-go-next` --- ## Visiting a Product on Polkadot Web https://docs.polkadot.com/reference/apps/hosts/polkadot-web/visiting.md How Polkadot Web resolves a .dot name and loads the resulting Product inside a browser tab, including the visiting flow that differs from Desktop. ### Sections - Introduction `#introduction` - The Visiting Flow `#the-visiting-flow` - How This Differs from Polkadot Desktop `#how-this-differs-from-polkadot-desktop` - Where to Go Next `#where-to-go-next`