Apollo iOS is a strongly-typed, caching GraphQL client, written in Swift.

It allows you to execute queries and mutations against a GraphQL server, and returns results as query-specific Swift types. This means you don’t have to deal with parsing JSON, or passing around dictionaries and making clients cast values to the right type manually. You also don't have to write model types yourself, because these are generated from the GraphQL definitions your UI uses.

As the generated types are query-specific, you're only able to access data you actually specify as part of a query. If you don't ask for a field, you won't be able to access the corresponding property. In effect, this means you can now rely on the Swift type checker to make sure errors in data access show up at compile time. With our Xcode integration, you can conveniently work with your UI code and corresponding GraphQL definitions side by side, and it will even validate your query documents, and show errors inline.

Apollo iOS does more than simply run your queries against a GraphQL server: It normalizes query results to construct a client-side cache of your data, which is kept up to date as further queries and mutations are run. This means your UI is always internally consistent, and can be kept fully up-to-date with the state on the server with the minimum number of queries required.

This combination of models with value semantics, one way data flow, and automatic consistency management, leads to a very powerful and elegant programming model that allows you to eliminate common glue code and greatly simplifies app development.

Getting started

If you are new to Apollo iOS there are two ways to get started:

  1. The tutorial which will guide you through building an iOS app using Swift and Apollo iOS.
  2. A Playground covering the concepts of queries, mutations, subscriptions, SQLite caching and custom scalars.

There is also comprehensive documentation including an API reference.

Releases and changelog

All releases are catalogued and we maintain a changelog which details all changes to the library.

Roadmap

The roadmap is a high-level document that describes the next major steps or milestones for this project. We are always open to feature requests, and contributions from the community.

Contributing

This project is being developed using Xcode 12.5 and Swift 5.4.

If you open Apollo.xcodeproj, you should be able to run the tests of the Apollo, ApolloSQLite, and ApolloWebSocket frameworks on your Mac or an iOS Simulator.

NOTE: Due to a change in behavior in Xcode 11's git integration, if you check this repo out using Xcode, please close the window Xcode automatically opens using the Swift Package manager structure, and open the Apollo.xcodeproj file instead.

Some of the tests run against a simple GraphQL server serving the Star Wars example schema (see installation instructions there).

If you'd like to contribute, please refer to the Apollo Contributor Guide.

Maintainers

Who is Apollo?

Apollo Graph, Inc. creates industry-leading tools for building applications with GraphQL:

  • Apollo Client – The most popular GraphQL client for the web. Apollo also builds and maintains Apollo iOS and Apollo Android.
  • Apollo Server – Build a production-ready JavaScript GraphQL server with a schema-first approach.
  • Apollo Studio – A turnkey portal for GraphQL developers, featuring a powerful GraphQL IDE (the Apollo Explorer), metrics reporting, schema search, and documentation.
  • Apollo Federation – Create and manage a single data graph composed of subgraphs that can be developed independently.

We are fully committed to advancing the frontier of graph development with open-source libraries, hosted software tooling, developer extensions, and community contributions.

GitHub

https://github.com/apollographql/apollo-ios