For my university senior project, I've been tasked with creating an Android app that will function as a HUD for the driver of a Formula Hybrid vehicle. The Raspberry Pi will gather all sorts of data from vehicle sensors (RPM, engine temp, battery temp, fuel level, ect.). The Pi then sends this data through some interface over to the phone (USB, presumably).
I could also go the route of using PiUI and could perform all design and implementation on the Pi itself, using the Android phone as a display only. However, this method uses WiFi in order for the phone to connect to the Pi-hosted server. I'm concerned that this method might not be in real-time.
In your guys' opinion, is there a preferred method? I think the most elegant solution is a dedicated Android app that interprets data sent over USB, and updates the UI accordingly. However, I have yet to find a way to interface an Android app to Pi software over USB.