Hello and welcome! :) I'm glad you're enjoying the game!
You don't have to worry about losing progress - the game will automatically detect your saves from older games and transfer them to the new version.
If you're on PC, Mac or Linux: Just update via the app or download the new version, extract to a fresh folder and play!
If you're on Android, just download the APK, extract and install it the same as you did when you first downloaded the game. DO NOT DELETE CK! That will erase your saves. Just install on top of the old version and play!
Hope that helped :)