Apollo Client Devtools is a Firefox add-on for the open-source GraphQL client, Apollo Client. This extension has 4 main features: 1. A built-in explorer that allows you to make queries against your GraphQL server using your app's network interface directly (no configuration necessary). 2. A query watcher that shows you which queries are being watched by the current page, when those queries are loading, and what variables those queries are using. 3. A mutation inspector that displays the mutations made to your Apollo Client application data. 4. A cache inspector that displays your Apollo Client cache data. You can explore the cache through a tree-like interface, and search for specific field keys and values. Code for this extension can be found at: https://github.com/apollographql/apollo-client-devtools Any bugs can be reported by opening a new issue at: https://github.com/apollographql/apollo-client-devtools/issues/new To learn more about Apollo, see: https://www.apollographql.com