Hard to think about but I have to say Pokemon Rumble World takes the cake in my mind for crappy games. I managed to play for free for a while but I've reached a point where it is next to impossible to progress further (unless I want to invest weeks into playing this barely fun game). If anyone wants to know specifics, I managed to get the silver balloon before running out of in game money and patience.
I got a bit of a kick out of it in the beginning cause the pokemon ran like pikmin and it was fun to play before going to bed when I was barely conscious. (fun fact: I have actually fallen asleep playing Prw and i accidentally spent 2 diamonds which was the last straw for me).
Everything in the game is too expensive , too unpredictable in terms of catching Pokemon, and the introduction of miis left a bitter taste in mouth I can't quite pinpoint.
Besides this game, I was really dissapointed in Stretchmo because you are only allowed to play the demo before having to spend money on levels. I could have seen myself enjoying the game as a puzzle lover but that was a serious turn off.
And one final unpopular opinion that people on this thread won't agree with: I like Pokemon shuffle. I haven't spent a dime on it and have managed to get really far (like to level 130s). I have had points where it got too hard for me and it took me a while to get past (Mega Gengar took at least a week). But if you save the daily coin cash and go through new event and expert levels, you can get more than enough money for the power ups to beat the levels. to me nothing is too expensive in the game besides the gems which are irl purchases. In terms of actual game play, the strategy is different from other games of the same calibur (ie Jewel Quest, candy crush *vomits*, etc) It has just enough of a challenge factor that makes levels more difficult and actually catching the different Pokemon provide a better advantage. I can see why other people hate it, but as a lover of stupid puzzle games, this one holds a dear place in my heart.