Here are some tips:
* Use adequate lighting conditions. The app will work better in daylight or strong artifical light, if your room is dull it will have trouble recognising what you are trying to scan.
* Scan the object against a white background. This will help the app distinguish what it is you are trying to scan, so use a white table if possible. What worked for me was simply placing a large white bathroom towel over my dining room table and then placing objects to scan on that.
* Pick an object that doesn't clash with the background. Out of curiosity I tried to scan a snowman teddy and it failed miserably given that it was mostly white against a white background. Try picking something with vibrant colours.
* Lay down whatever it is you're scanning and allow the app to detect it by raising the camera away from it. Once it's detected you can move the actual object rather than move the phone, which is awkward to do while keeping the subject in the shot.
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