Tell me about some useful retouching software in your mobile phone.

Snapseed, the best mobile phone software used so far, functions like a small ps, which is very easy to use (ps, I took a class for a semester, and now I almost forget it, crying ...). Just open a picture and fool it, and you can basically understand its function. In fact, I don't need to read too many tutorials. The biggest reason I like it is that it can make photos more textured (common functions: highlighting details, HDR scenery ...)