Create an app that has two activities, buttons to move between them
and a way to change something on each.

Move back and forth between the activities by use of a button (at
least one button will exist on each activity).

Pass some information in the "EXTRA" portion of the intent to each
activity such that the information is used to change "something" in
the other activity. What changes is your choice (by default you could
simply affect textviews if you like), but think about trying something
new like changing an image or background to get some more exposure to
other UI elements. Demo your app to me for credit.