I cannot state this with absolute authority, but based on my own experience with the LG L34C in particular and computers in general, it sounds highly probable that
your smart phone is running out of RAM as you play your game. When you reboot your phone, the RAM is dumped and you are able to begin playing again. You may well ask: "
OK, so how do I get more RAM?" The answer comes back:
You Don't..
.not unless you hack the phone by rooting it and then seeking the advice of those knowledgeable with apps available for Android which one(s) will permit you to assign more of your available memory to function as RAM. Here is one hint I CAN share with you:
Get thyself a 32Gb, Class 10 microSD Card to supplement thy phone's paltry 2 Gb of available, built in memory!
Cheers!