Hello there and sorry for the late reply!
If there is an error message, then it could be a bug that we can solve. Feel free to send us an error report so we can look into it.
If there isn't any, then it's an "out of memory" error, which means that your device force closes the game because it was asking for too much RAM. In this case, you are right, you should try to set all graphical option to SD and put ambient sound to 0 in the option.
Did you get the last version (1.13)? There is a special option called texture compression that should help a lot to prevent stability issue.
Finally you should note that we don't put any hard limit on village growth, however very few devices can make the game run with more than 150 followers.
Cheers!