I've downloaded and installed the application and used the on-start tutorial to complete a drawing. Afterwards, I tried to create an account to get to the Outline feature, but the software is having an issue because every time I try to log-in it says Internet Connection error while the phone is connected to the Internet.
However, I see that I have the possibility to browse Outline drawings, but that's it. You can't make one by yourself. As for the feature images, you would have to upload it to gallery and then if it's voted by users, it will appear as a featured image.