When you edit a value of a certain item of the DataGrid and keyboard is displayed, while the focus is still in the input and the row is scrolled away, the keyboard will stay open on Android.
In addition, if you return back to the edited cell, the row will display as if it were on focus, the cell shows the editor underline, the keyboard is still open, but there will be no focus. You will be required to click on the cell to get focus again.
Lastly, only on Android 5.1, if the edited value is a number, when you scroll the cell out of view, the keyboard changes from the numerical to alphanumerical (default).