I haven't used it yet but know there's this widget that might be of help? Keyboard Avoiding View https://appstore.home.mendix.com/link/app/114461/
-EDIT- In the documentation it says that it isn't suitable for textbox/textarea.. My bad
I usually put the input elements in a scroll container, be sure to set its size to Maximum space. The scroll container helps to allow the user to enter text into the input elements. If you want to, you can put a container above the scroll container to place buttons in, these will remain visible with the keyboard open.
Android handles the dataview footer nicely: any content in there will be visible between the keyboard and the input elements in the scroll container.
The app should handle it, bit it would also be possible to build a pluggable widget to set the focus on a specific input field, if necessary. I've done something similar before.