Hidden tips, tricks, settings, etc. - opencardev/crankshaft GitHub Wiki
When you park the car
Just unplug the phone, the screen will go to sleep after 30 seconds. Just plug the phone back in to wake it up.
Development mode
As Crankshaft is designed as a "plug-n-play" solution, it mostly doesn't need to be configured. But if you want to save the settings or change the system, you could do so by starting it in dev mode.
Turn on the Pi with a button
The solution is discussed here.
Use the control on your steering wheel
Many actions built on to your steering wheel can be modded to serve as triggers for actions in Android Auto. One rough guideline is detailed here. There will be more documentation coming in the future, so stay tuned.
Customize Crankshaft: Use a wallpaper!
OK Google
OK Google works, you need to buy a microphone like this and plug in the USB port of the Pi. The linked microphone is not an affiliated link, it's just a cheap basic microphone that has a long wire and has been verified to work with Crankshaft.
Saving Power
If you want to keep the Pi running to avoid reboots during ignition, you can have the Pi and Touchscreen powered separately. By powering the Pi from a constant power source and the screen from the running/ignition source, it will keep the unit running and only restart the touchscreen. However, given that a Pi can take anywhere from 5 to 10 watts (depending on settings such as overclock, fan, WiFi, BTLE...), it is likely you will drain your battery enough to kill it should you not drive it once every few days. Assuming 10 Wh discharge, you're looking at 240 Wh every day and almost 1 kWh every 4 days. Assuming 5 Wh, you're looking at half of those numbers. With a regular 12v 50Ah battery (600 Wh), this will run the Pi for two and a half days (60 hrs) to 5 days (120 hrs) on a single charge. YMMV.