When you zoom the 25k map, there is no extra detail beyond that normally present at any magnification as far as I can tell. The high zoom levels are useful for micro-navigation such as finding your way through farmyards or being on the right side of the hedge. I did have a problem with the recentre and compass but that was cleared by a recent update. My main criticism now is you cannot simultaneously follow a route and record a track - a feature that is available in both Garmin and ViewRanger.
For info: I am using OS Version 2.0.3.726 on a Samsung A50 running Android 9 patched to 1 Oct 19. The last OS app patch was released this week.
I agree not extra detail but easier to see when zoomed right in and it does make a difference, more than I thought it might...at least to my old eyes
.I need to see if I get an update offered...