The Accounts framework provides access to user accounts stored in the Accounts database. An account stores the login credentials of a particular service, such as Twitter, that can be used as authentication for the service. By implementing the Accounts framework into your app, you do not need to be responsible for storing account logins yourself. Instead, the user can grant access for your app to use their account login credentials, bypassing the need to type their username and password. If no account for a particular service exists in the user’s Accounts database, you can let them create and save an account from within your app.

The most powerful, yet lightest weight crash reporting solution for iOS and Android developers. | Crashlytics

A full suite of services created by the team that brought you Crashlytics. Fabric provides monetization, engagement and other uses for developers beyond crash reporting.

Apple's new Swift programming language has brought iOS a new set of APIs, design patterns, and tools. With the Facebook SDK for Swift, you gain a swift-taylored experience for all of the core Facebook SDK for iOS's APIs.

GTMSessionFetcher makes it easy for Cocoa applications to perform http operations. The fetcher is implemented as a wrapper on NSURLSession, so its behavior is asynchronous and uses operating-system settings on iOS and Mac OS X.

Render advanced 3D graphics and perform data-parallel computations. Get fine-grained access to the GPU while minimizing CPU overhead. The Metal Framework provides extremely low-overhead access to the GPU, enabling incredibly high performance for your sophisticated graphics rendering and computational tasks. Metal eliminates many performance bottlenecks—such as costly state validation—that are found in traditional graphics APIs. Metal moves all expensive state translation and compilation operations out of the critical path of your most performance sensitive rendering code. It provides precompiled shaders, state objects, and explicit command scheduling to ensure that your application achieves the highest possible performance and efficiency. Graphics, compute, and blit commands can be used together seamlessly and efficiently. Metal is specifically designed to exploit modern architectural considerations, such as multiprocessing and shared memory, to make it easy to parallelize the creation of GPU commands.

Nanopb - protocol buffers with small code size

Protocol Buffers (a.k.a., protobuf) are Google's language-neutral, platform-neutral, extensible mechanism for serializing structured data.

Use the Safari Services framework to integrate Safari behaviors into your iOS app.