Go to my library
then click on download :)
do I have to uninstall the previous version? and if I have to... do I have to reinitiate the game?
no need to uninstall the previous version. The only exception is Android. if you want to replace the demo, you'll have to uninstall it first (and lose your save). But from 4.2 to 4.3 and next, you can just overwrite
