{HEAD ~ Embodiments} of the disclosed technology comprise a handheld display device with {TAIL ~ built in accelerometer} and, in some embodiments, compass 
{ HEAD ~ Embodiments } of the disclosed technology comprise a handheld display device with { TAIL ~ built in accelerometer } and , in some embodiments , compass
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH