Apollo Kotlin is a GraphQL client for Kotlin/JVM and native apps, supporting custom scalar types with adapters.
Field note
Apollo Kotlin is a strongly-typed, caching GraphQL client for Kotlin and Java. This page explains how to define custom scalar type mappings and adapters, register them at build time or runtime, and use built-in adapters.
Capabilities
Tags
Ways to use it
Kotlin / https://www.apollographql.com/tutorials/apollo-kotlin-android-part1
Kotlin / https://www.apollographql.com/docs/kotlin
Product features
Built-in adapter supporting String, Int, Double, Boolean, List, and Map for intermediate steps.
Create an ApolloClient instance connected to the remote server.
Support for AppSync and graphql-ws websockets.
Automatically persist queries to reduce network overhead.
Binary breaking changes only in major versions; source breaking changes avoided in non-major versions.
Register adapters in build.gradle[.kts] via mapScalar with a third argument.
Each class requires an adapter with fromJson and optionally toJson functions for network serialization.
Define a mapping in build.gradle to tell Apollo Kotlin which class to use for each custom scalar.
Support for custom scalar types in GraphQL schemas.
Learn about enum types in GraphQL.
Additional adapters for dates and big decimals available from apollo-kotlin-adapters repository.
Generate fake models for testing.
Fragments can share result handling between queries and mutations.
Mutations are represented by generated classes conforming to the Mutation interface.
Provides HTTP caching capabilities.
Access fields of polymorphic types.
Input objects are passed as mutation variables for complex values.
Reflect queried data in the app using Jetpack Compose.
Reusable sets of fields across multiple operations.
Default codegen that merges all .graphql files before generating models.
Support for GraphQL queries, mutations, and subscriptions.
Combine multiple queries into a single HTTP request.
Parsing without using reflection, enabling safe optimization and obfuscation.
Register adapters on ApolloClient instance using addCustomScalarAdapter.
Add the GraphQL schema to the project.
Follows semantic versioning with pre-release, alpha, beta, rc, and stable versions.
Symbols marked @ApolloExperimental are not part of public API; @Deprecated symbols removed after major version and 6 months.