Chinese malware creeps have created a Android app that allows anyone to generate a fully-working Android ransomware just by filling in a form and pushing a few buttons. The app is currently available on Chinese underground hacking forums and via Chinese social media networks.
The app is currently available for Chinese at this time, but its a matter of time that it will be available in other languages.
Be sure to back up your phone daily no matter its Android, iPhone or Windows. A good daily backup will ensure you have the ability to restore your phone to the way it was. Another good practice would be to backup your phone before you install any new app.