I think that when an editing function is selected, it should stay active until another function is selected. For instance, if I'm adding text (A) in a score, I need that it stays active until I select another function such as "Marker" or "Pen", etc. If I'm writing or highlighting something, the same... It'd help to save lot of time ... and patience... ;-)
I can see arguments for it working both ways. Sometimes it's nice to be able to quickly reposition an annotation after creating it. If the tool stayed active, that wouldn't be possible. My idea was to support a mode to lock the current tool by long pressing it. With the upcoming annotation rework, I'm going to have to handle some of it differently, so I'll have to think about how I want to toggle the mode on or off for locking the current tool.
Mike