Which iPhones does it work on?
Finger Paint Duo needs an iPhone Duo. The app is built around folding the phone shut, so it does not run on iPhones that do not fold.
How do I make a print?
Open your iPhone Duo flat and paint on the inside screen with your fingers. Fold the phone fully shut, wait a moment, then open it again. Your painting will be mirrored across the hinge.
I folded the phone and nothing happened
Make sure the phone closes all the way before you open it again. A half fold does not count as a press. If it still does not work, close the app from the app switcher, open it again and try a new painting.
Does the app collect any of my data?
No. See the privacy page for the detail.
Still stuck?
Email moc.eivadsemaj@semaj and say what you were doing when it went wrong and which version of iOS you are on. A screenshot helps.