The most popular app of late has been the simplistic app, Flappy Bird.
Most known, because the founder took it down for a bit this app made a huge splash in the community. People realized that apps don’t really need to be massively complex to be successful.
I think the two things that made this app successful was the look of it and the challenge. People love to be challenged when they play apps, but it has to be a quick challenge. The community enjoyed being instantly challenged when they opened the app. Also, it had a very cute look to the app, which made is aesthetically pleasing to the player.
I must say I enjoyed trying to beat my own scores immensely and I think the app did a great job at sticking to its roots of challenge. Overall I would give the app a 9/10. I hope the developer comes out with more apps soon!