1) They find your app 2) They want your app
Posting on relevant message boards, forums, twitter and the like well help with #1. For #2, you have to frame your description and talking points to the pain point that your app addresses.
#2 will help you figure out where to post and how to describe you app. What is it that you've built?
My first thought was that it was a game! I guess the lenses through which you view the world make an even starker difference than I'd already thought.
1) Fun caused by learning—whether if it's an 80's style sidescroller a racing game or a RTS, many many games are about steadily mastering skills and using them to take on progressively harder challenges.
2) Immersive stories—RPGs can offer many of the same benefits of either reading fiction or watching movies. This type is pretty rare on a mobile device, but certainly not unheard of.
In either case, a game is something I'd actively seek out, not a way of escaping "pain". I certainly don't feel a "pain" of boredom that needs to be relieved. I'm just not that morose.
For example if you're playing a game to learn, you can view that as trying to escape the pain of ignorance.
There's nothing morose about it.