Automatically add date/time and sequential number to new GPS points in the field

We are using a tablet running QGIS 3.4.9, connected to a bluetooth GPS device, to record data in the field. We create GPS points using the "Add Point" button in the GPS panel. After tapping on this button, we can fill in attributes manually.

Is there a way to set it up so that the date/time and a sequential index number is added automatically to each new GPS point? (Preferably without having to use Python.)

For the sequential index number, we cannot use rownumber because the points are added in a seemingly random order. For example, the last point added is usually not the last row in the attribute table.