Objectively, unless you are very good and lucky or incredibly lucky, you will make little or nothing. The mobile gaming market is littered with great projects which have had a lot of time and money spent on them that sank without trace. The market is just too crammed full of competitiors after the same money.
But then again, there's things like Flappy Bird. But that's pure luck. It's not that good a game, it's not remotely original, it's not that well implemented and the graphics are nicked from Super Mario. But it took off.
Nobody really knows why it took off though.
The other thing is to find a niche that no-one else is in, say simulate a sport that isn't that popular worldwide but has devotees, like, say, Curling. You might not get many sales, but you might be in a niche on your own.
If you are producing the sort of game Construct 2 does very well "out of the box" you are reliant on luck no matter how good your presentation is.