Actionscript 2 (AS2)
Motion tracking is very effective and inexpensive compared to touch screen, as it is completely backwards compatible. Even modern smart phones are integrating full flash into there systems, not just flash lite/mobile.
More 'AR' Information:
AR - Augmented Reality technologies use flash and motion tracking to great effect.
Motion tracking using the SWF Iframe Embed method
<embed src="http://sites.google.com/site/drupalvsgoooglesites/4sides_controls_v1-000-test01.swf" width="600" height="650"></embed>