Automated UI Testing using the Automation instrument included with Instruments for iOS development. Not to be confused with [xcode-ui-testing] which was introduced in Xcode 7.
Instruments is an application shipped with Xcode and used to help profile applications in both iOS and OS X development. One of the tools included with Instruments is the UIAutomation instrument which allows for automated testing of user interfaces using scripts written in JavaScript. This functionality was introduced with the iOS 4 SDK.
This tag specifically focuses on using this functionality in relation to iOS development. These scripts can be used not only to automate a user's interaction with the application, but they can also contain asserts which can test if the application is behaving according to the developer's expectations.
For the new Xcode 7 UI Testing feature, see xcode-ui-testing.