This app was mentioned in 2 comments, with an average of 2.00 upvotes
Perk Screen https://play.google.com/store/apps/details?id=com.perk.screen is an app that reward you for unlock your screen. The new update (2/9/2015) will not reward you points if you don't login with facebook for the app. You can make easy 250 points daily if you got the fast fingers.
I use this one. This company has a bunch of game apps, too. I used them on my iPhone so when I switched to Android I got them, too.
https://play.google.com/store/apps/details?id=com.perk.screen