Hobbyking sells a neat wifi receiver to control planes and cars using android or IOS devices. So I bought one and used my computer and a gamepad to control a motor.
A description of the receiver protocol can be found at rcgroups forum
"If someone is interested: The HK Wifi Unit can be used with any WIFI enabled device. Though I do not have a unit, I just checked out the code. The HK Wifi unit waits on IP 10.10.100.254 on port 8899. The socket timeout should be set to 1000ms. One message has a length of 11 bytes. The first 4 bytes are always 85-0-11-0. After that, the values of the 4 channels are transmitted in correct order (channels 1-4). The next 2 bytes (9,10) are not used at all (maybe space for another 2 channels in the future). The last byte is reserved as control byte. All 10 data-bytes are added and transmitted as last byte. I hope I could help you. I do not have the time to develope an android app at this very moment, but it should be really easy. Hope to see some in the near future."
The output from gamepad is a float between 0 and 1. I have defined the base power as 50, so for each .1 incremment in gamepad input, the motor increase it power in 5 units going to a maximum of 100.