seriously, I don't get it. There are tons of off-the-shelf electronic kits that already do this (ARM, PIC, AVAR, etc)... And most of this is just simple logic. Follow a light beam, follow color, bla, bla, bla... Anything really useful, to me, appears one would need a bit more than a smart phone. Honda's robot comes to mind and that quadraped that supposedly is suppose to help military carry heavy things through tough terrain.