Registration
You frame your prayer mat from above using the on-screen outline. prayd creates a local visual signature used for later comparisons; it does not upload the image to a server.
Scanning after prayer
Hold the phone roughly square to the mat and let it fill the guide. The app requires several matching frames and a deliberate three-second hold, so a single accidental frame cannot unlock.
Why framing matters
Whole-image matching is sensitive to composition. An overhead view of the full mat is more dependable than a close-up of a corner or fringe. Use similar framing during registration and scanning, with enough light to see the full mat.
If the camera gets it wrong
Keep the mat in frame and improve the light. If matching still fails, the “I prayed without a prayer mat” option appears after 12 seconds. It exists because a verification tool must never strand someone who has actually prayed.