Just install the itch app and it'll run the linux version for you. Just easy. https://aur.archlinux.org/packages/itch/
But I'm on 14.04, the Itch app isn't for Ubuntu 14.04!
you can get a precompiled binary here: /app - Lets hope it'll workmaybe there is also an PPA for Ubuntu - I dont know.
Update: I'm on 16.04 now and the Itch app works now. Thanks for the help!