SDKS

The same purchase flow, in every language you ship.

Native purchases. Verified access. Swift and Kotlin SDKs, web packages, and a REST API for your backend.

Swift · Kotlin · TypeScript · REST

1import CashSDK
2
3// Configure once. Build something great.
4CashSDK.configure(publishableKey: "csk_pk_your_key")
5
6// Start a purchase with your store product ID.
7let result = try await CashSDK.shared.purchase(
8    "app.example.pro.yearly"
9)
10
11// Server-verified access, ready to use.
12if CashSDK.shared.entitlements.isActive("pro") {
13    unlockPro()
14}

Native iOS · StoreKit 2UTF-8

Native clients. Your own billing.

SwiftiOS & macOS

KotlinAndroid

TypeScriptWeb & Node.js

RESTAny backend

ChromeExtensions

StripeNo client SDK

Native where it counts, cross-platform where it helps, REST for everything else.

SDKsQuickstart Type-safety Platforms Integrate

Start for free

Type-safe

Autocomplete your way to a paid app.

Offerings, packages, and entitlements are fully typed, so your editor (and your coding agent) knows the shape of every response. No stringly-typed product IDs, no guessing which fields exist. Mistakes are compile errors, not production refunds.

Typed offerings & entitlements
Nullable-safe entitlement checks
Generated types stay in sync with your catalog

Purchase.swift

1let offering = try await CashSDK.offerings()

2offering.

monthlyPackage

annualPackage

lifetimePackage?

identifierString

packages[Package]

Generated from your catalog

App Store

iOS

Swift, StoreKit 2 and native paywalls for iPhone and iPad.

Released SDKExplore

App Store

Mac App Store

StoreKit purchases on macOS and Mac Catalyst, with shared customer access.

Released Swift packageExplore

Google Play

Android

Kotlin, Play Billing and server verification for your Android app.

Released SDKExplore

Your Stripe account

Web

TypeScript and React clients with authenticated customer sessions from your backend.

Released npm packagesExplore

Your Stripe account

macOS with Stripe

A native Swift commerce client for direct distribution, with system browser checkout.

Released Swift packageExplore

Your Stripe account

Chrome extension

Manifest V3 pages and service workers, with checkout attempts preserved across restarts.

Released npm packageExplore

Your Stripe account

Stripe only

Keep your checkout and read customer access from your backend. No client SDK required.

Generally availableExplore

One purchase model

Write the entitlement once. Ship it everywhere.

The same entitlement logic, from native iOS to the web: one purchase model behind idiomatic SDKs.

iOS & macOS / Swift

StoreKit 2 native with async/await. The same package runs on iOS and macOS, Mac Catalyst included.

Android / Kotlin

Play Billing v9 wrapper with coroutines.

React Native & Flutter

On the roadmap: one bridge over both native billing stacks.

Web & REST

Browser, React and Node.js packages, and the REST API. Identical entitlement model.

Integrate

From install to first purchase in four calls.

Install

Add one dependency with your package manager of choice.

Configure

Initialize once on launch with your public API key.

Fetch offerings

Load the current paywall and pricing from the server.

Purchase

Call purchase and read the returned entitlement state.

~/your-appiOS simulator

✓Load sandbox configurationdone

✓Open the sample purchase flowdone

✓Receive verified accessdone

if CashSDK.shared.entitlements.isActive("pro") {
    unlockPro()
}

folio.You’re ready to create.pro: active

Illustrative flow · no SDK connection

Built for the coding agent doing the wiring.

Lightweight

Small footprint, full coverage

7Platform and billing choices

TypedEnd to end

1 keyTo configure

~1 hrInstall to first purchase

ONE CONNECTED PURCHASE FLOW

CashSDK

Store receipt

pro active

A purchase startsproduct: "pro.yearly"A familiar checkout, in your app.

Illustrative flow no live transactions

Explore the platform

The SDK is one call into the whole stack

Everything the purchase flow touches: the paywall it renders, the receipts it validates, the events it emits.

Paywalls

Design the purchase screen and ship it over the air. The SDK renders it natively.

Explore

Receipt validation

Every purchase is validated server-side before the entitlement unlocks.

Explore

Webhooks

Get a signed event the moment a purchase, renewal, or refund happens.

Explore

Add CashSDK to your app today.

Choose your platform, connect billing and verify the purchase flow with your customers’ identities.

Read the SDK docs Start free