When the display turns off, the game crashes

[wordpoison]

After a minute or two of non-use my display turns off, the game will crash and I will have to redo the entire stage I was on.
This also occurs, if I just turn my display off, or hit the home button.

[lunker2]

After a minute or two of non-use my display turns off, the game will crash and I will have to redo the entire stage I was on.
This also occurs, if I just turn my display off, or hit the home button.

same on nexus 5 (android 4.4.2)