@pratik If one is using iA Writer to write a post it’s as simple as tapping the Command Keyboard button (onscreen shortcut) which has an option to add a photo to the current document. That brings up the Photos chooser. That will insert the photo. Done. Unfortunately it only allows one photo at a time.
It’s possible to then just publish the draft straight to micro.blog and it will bring up the draft ready to edit in browser.
The only downside of this method is that there is no setting for the save location or quality size of the saved image on the local device. It just places a jpeg into the same directory as the text file you are editing.