The last three pictures I posted were done with Open Camera on LineageOS.
I must admit, that I usually take several shots and only keep the best one.
Macros are sometimes easy, sometimes difficult. Depends on the light, contrast and especially the size of the object.
When the camera cant get the correct focus, I let it focus at another object at the same distance, pan back to my subject and focus again. This way I often succeed when subjects are too small.