Now I barely use the Samsung Gallery (only for video edition) and never the Google Photos. Here are some findings based on v1.0 (81).
Bugs or Inconsistencies
- Error using Draw “This image can’t be loaded for drawing”. This happens if you make a change (crop for example) and you engage the Draw tool without having refreshed the Gallery. It doesn't happens with other tools
- Overlay text always reappear when we get back to the gallery and open another picture
- Resize/Convert suggest "Save a copy" by default whereas it's "Save" for all other tools
- Resizing tool is not visible in the list of tools whereas it's one of the most used (e-mailing, archiving,...). I suggest it should be named Resize/Convert
- A mean to quickly delete photos or videos while navigating through images in full screen. Cleanup is a daily job

- Manage multiple files currently not allowed for Edit, Draw (Watermark yes !?), Crop/Rotate whereas this can be useful. For example, in case of multiple pictures taken in same place or in rafale mode and ensure consistency in the results.
- Resize/Convert multiple files. Allow file size estimation at least for the first in the list. The workflow should be very similar to the one for a single file.
- At time of saving, file size estimation should be always visible for tools influencing size like cropping, drawing, adding an image, resize or convert (the button doesn't look valuable). In case of multiple files, estimation for the 1st file should be enough
- Filigrane & Draw looks duplicate but "Add Image" is a feature missing in Draw
- From the Thumbnail’s view, a button to go to the related Album (folder)
- Manage, restore dates/times for videos as most tools managing videos erase or reset these metadata.
- Set metadata date/time based on timestamp in the filename. I managed to create scripts (.cmd) to do that on my PC and I'm reluctant to start equivalent dev’ on Android
- Convert to PDF