Not enough caching
I've noticed a lot of complaints that seem to stem from similar issues; badge loading time, startup time, etc, all seem to be tied to one thing: network performance. This is likely not all necessary. Why are the badges not simply cached/cacheable on the user side to avoid loading them into memory every time a profile is opened? Why does the game need to wait to start to load frequently visited maps, portals, etc? I understand that not ALL of this can be cached, but surely a 50-100 MB cache could make a substantial difference in performance on the app in various places, vs using the limited mobile data of players. Perhaps a cache of portal images that could be cycled every X portals would help as well.
I understand this won't fix most things, but an improvement is still an improvement, and I feel like this could go a long way for many on slower networks, limited data, etc.