[Portal Scans UX issue] Location of "Retake" button causes accidental portal scan loss
As you can see in these two screenshots, the vertical distance from the bottom of the screen is about the same for the "end scan early" button and the "retake" button. When ending a scan manually after the red stop button becomes enabled, sometimes the scan will automatically end before you can manually hit the red button and then, because the game has switched to the "upload now/upload later/retake" menu, your finger lands on the "retake" button, resulting in the loss of the scan that you just took.
This has happened to me numerous times while scanning and is a regular source of headache.
My proposed fix for this problem is to add a confirmation prompt to the "retake" button