Our admin and sales team members's access profile grants them Full Access (so they can see all team member's tasks).
When I view the calendar on the Android mobile app, I see a whole bunch of tasks that aren't assigned to me, but rather are assigned to other team members (image 1). If I view my calendar options, I only see my own calendar selected (image 2). It does not make sense that I'm therefore seeing other folk's tasks.
After some trial and error, I found that if in my calendar options I add the calendar of my other team members, and then remove them, then and only then could view only my own tasks.
Also, when I do select to view another team member's calendar from my options, that setting does not stick. As soon as I back out of the options menu, and then view it again, I only see my own calendar selected. The other team members disappear, which definitely seems like a bug. I tested this on multiple different Android devices.