There is not much source code to judge this by, the android dir of the source repo https://github.com/intel-isl/OpenBot https://github.com/intel-isl/OpenBot is

There is not much source code to judge this by, the android dir of the source repo https://github.com/intel-isl/OpenBot https://github.com/intel-isl/OpenBot is currently empty. But you can run ROS nodes on an android phone and maybe talk to the Arduino through a serial-to-USB port on the phone?