How to Backup Android Phone Applications and Games Data using Helium APK

Based on my experience, i like to change ROM but when I change my Android Smartphone ROM of course the app and the DATA will also be erased (as the wipe data process). It's sucks that i must re-setting my apps again and the worst is i must start my games like GTA, Final Fantasy, etc again from zero -_-. So searching in the internet i finally found how to backup all my apps and games data using