It doesn't seem to me "tamper-evident", more like "tamper-verifiable", you need both the app and the reference initial photo to determine whether it was tampered with or not.<p>Besides, it looks like they will need to add a notch, an axis, <i>whatever</i>, to make the reference photo and the camera view easily aligned, (or would the app automagically do an up to 360° rotation until it finds the "right" pattern?).<p>Maybe it is just me (and the poor android phones I am familiar with) but often even reading a QR-Code is difficult (due to lighting, angle of view, reflections and what not) I imagine that a "round" QR-code without the "corner dots" would be extremely difficult to scan/compare.