Here's two different, but similar Rules. Either one will do the trick. Which one do you prefer and why?
For something like this I always use example 1, its simpler and in some way more focused , also rule priority does not get in the way. As to whats quicker, its hard to say, probably never know the difference - not sure in the Mobile context , should be the same ?
IMO, I don't think "WAS CHANGED" was meant for this kind of scenario. AwareIM basically does its own checking in the background. WAS CHANGED only becomes relevant if something else needs to happen by the event.