CACHE APPS / USAGE
I really like the integration efforts to move all of MS Office 365 Services into a single app... but it becomes extremely frustrating when you switch from one app to another.
For example, I've added a 'Planner' tab and a 'Notebook' tab to one of my channels... when I switch between the two, Teams re-loads the entire Plan/Notebook, and I don't resume where I left off.
So much wasted time in page loads / finding where I was to move forward.
Kyle S commented