According to the chart, Simlink (as Support for moving maps in Navigraph Charts app on external devices) is sadly not included in the JustFlight Piper Fleet.
However, “Jeppesen airport charts and diagrams in virtual cockpit” and “Navigraph enroute charts in virtual cockpit” are seemingly included, and those might include an aircraft icon displayed at your present position (only on charts that are geo-referenced, obviously)— but only inside the virtual cockpit rather than on an external device as well.
I don’t have the PA38 nor Xbox, but my guess is the charts will be displayed on the tablet here:
Given they’re probably not integrated into the avionics (unlike on a G1000/3000/5000) it’s also possible there will be no icon indicating your aircraft position at all.
Regards,
Tim