If you have two apps, both maps...

The reason behind it is the hardened memory allocator, which seems to create a significant overhead for Osmand. That might be because scrolling a map requires constant loading and discarding of data.

... is this really the right hunch, over e.g. the OpenStreetMaps app lacking in discipline with its heap allocations?

There needs to be a wall of shame for apps that abuse hardware owned by users