Official Quickblox iOS SDK by Quickblox. It provides a link to download the SDK, code samples, and references to add the SDK to XCode and connect to the cloud. To have an idea of the integration possibilities, visual examples present how to create a simple WebRTC, a chat, a localization feature, and a content storage.
Our API directory now includes 50 backend APIs. The newest is the CloudBees API. The most popular, in terms of mashups, is the CloudMine API. We list two CloudMine mashups. Below you'll find some more stats from the directory, including the entire list of backend APIs.