Some apps include personal app capability, allowing you to use them extending beyond a channel or chat, but still inside Teams.
For example, OneNote allocates you a private workspace within Teams, while Planner and Wrike provide a bird’s eye view of entire tasks, throughout boards that you or your team have included as channel tabs.
Add a personal app
Locate Apps on the left of Teams, then explore or browse the app categories to discover new ones. Search for ones with Personal app stated as a capability.
At this point of adding the app process, simply click the Add button!
Access or pin a personal app
On the left side of Teams, press to access any app you’ve inserted that supplies a personal view.
Right-click any app icon to Pin it for fast access.