- GApi - The Objective C Google API library - JSON services. Newer. I will be using this.
- GData - The Objective C Google Data library - XML services. One tiny portion of it is a small, simple wrapper for working with XML on iOS. I use this every day. Includes examples of accesssing each service. For instance: Calendar, Google Docs.
- Google Fetcher - wraps NSURLConnection. An easy way to make web requests. I use this every day.
- Google Toolbox - The Objective C Google Toolbox for Mac (also iOS). Lots of useful code here. Great tools for unit tests on iOS.
- OAuth2 - The Objective C Google OAuth2 library. Manages: UI for asking the user for credentials, securely storing them, and using them to sign HTTP requests. Use this for making requests on Google services where you must be signed in.
- Source Code - my source code, most for OS X, Macintosh and iOS.