Why the table? Just place the tablet on your laps and use both hands (vigoriously ;).
There are many techniques - the advanced players use most of their fingers constantly. Touch controls could be very elaborate and precise.
Because that seems incredibly awkward and uncomfortable?
Playing on the table is one way - but it hurt my neck too much. I preferred the "claw grip" on my phone while laying on the couch - though I could only comfortably do 3 fingers. Some of the best mobile players do 6!