On Lightroom for Android, It would be great to have an undo button for the last action when rating pictures. Let me give a example. I filter my photos to only show those that have not been rated yet (or flagged) and as soon as I flag them either as picked of rejected they disappear from view. Therefore if you make a mistake and reject one that you meant to pick the only way to fix this is to go back to the album view and cancel the filtering so that you can see all the pictures and find the one you mis flagged and correct it.
- Thank you developers for making Lightroom better every day!