Overview

MCP Mobile is a set of small native adapters around the official MCP SDKs, for apps that need an MCP client.

Android uses the official Kotlin SDK; iOS uses the official Swift SDK. This repository owns mobile connection ergonomics, cancellation, credential integration and native authentication helpers. It does not implement another MCP protocol stack or ship a chat application.

The Cully apps are the first consumers. App UI, model inference, skills, task policy and service URLs stay in Cully. Other apps configure their own servers.

0.1.0 preview

	Android / JVM	iOS / Apple platforms
Upstream	MCP Kotlin SDK 0.15.0	MCP Swift SDK 0.12.1
API	Kotlin suspend + Java callbacks	Swift actor + async/await
Connection	Streamable HTTP/SSE	Streamable HTTP/SSE
Tools	Discovery, pagination, invocation	Discovery, pagination, invocation
Credentials	Host-supplied current bearer token	Host token provider or upstream OAuth authorizer
Native helpers	Cancellable Java requests	System-browser OAuth presenter, device-only Keychain token storage
Minimum	Android API 26+; verified on API 30	iOS 16+, macOS 13+, Swift 6.1

Both adapters enforce HTTPS, with explicit loopback HTTP for development. Operations have bounded timeouts. No offline tool-call queue or wrapper-level automatic replay is added. Kotlin disables redirects and OkHttp connection retries; Swift uses the upstream Foundation transport and its configured OAuth challenge recovery. A cancelled action may already have run on the server.

This is a preview. See verification for the tested environments and remaining device checks. There is no paid model API or inference dependency in this SDK.

Where to go next

• Android and iOS: installation and first client.
• API guide: client signatures and lifecycle rules.
• Architecture: who owns what between your app, MCP Mobile, the official SDK and the server.

Checks and release packaging

mvn -B verify
swift test --jobs 4                # Xcode includes XCTest
swift run --jobs 4 MCPMobileCheck # Also works with Swift Command Line Tools
python3 scripts/package_release.py

The opt-in live test reads CULLY_MOBILE_SESSION_FILE, a private JSON file with endpoint and a fresh access_token. It discovers tools and makes one bounded read-only Cully context call. Never commit that file, credentials, server content or device transcripts. Public CI uses fixtures and does not require a Cully account.

Migration

The old Expo app and custom TypeScript @mcp/core have been retired. They remain in Git history. There is no TypeScript package or React Native bridge in 0.1.0. Native Cully app sources live in tavric-labs/cully/apps; this repository is reusable SDK code.

See also the plan and third-party licenses. MIT license.