It is now possible to revoke and edit messages on the beta version of WhatsApp for iOS. This is a long-awaited feature that could prevent awkward moments when users of the app send a message to the wrong person or perhaps fell victim to poor word choice. According to The Telegraph, a message would only be remotely deleted or edited on the recipient"s device if it had not yet been read.
Another new feature released with this update is the ability to track another user"s precise location. This is currently called Live Location Tracking and requires the tracked user to authorize its usage for one, two, or five minutes. It is speculated that this feature can only be turned on manually by the user, which, if true, should address potential privacy concerns.
At present, there is no information regarding the general availability of these features or when they would arrive on other platforms.
Source: The Telegraph via MSPoweruser