Most of the screen shots you see where I have added lines/arrows, shapes and text are done on my PC with a free program called Paint.Net (PaintDotNet).
I don't do much image editing from Mobile. I downloaded an app called Screen Master to get screen shots. (The Android native screen shot function seems to upset Diggy.) With Screen Master...
- You can crop.
- You can add basic lines, circles, and rectangles (about 10? color choices).
- You can add text (about 10? color choices).
- You can also "stitch'"a series of screen shots one after another, which comes in handy.
On my Android S6, the app gives a very small area to work with and it can be challenging. Hard to get near an edge. Maybe I should try a stylus.