- A volume knob! This is by far the best way to control volume. I like to feel the controls in a car and not have to look at them. I also like to directly adjust to me desired volume level as quickly as possible. Driver distraction is a huge problem and touch screens or controls that you must look at contribute to this problem.
- Android or Android Auto. You can find both. I would also like the option for the new Android Auto wireless support.
- Backup camera support. This one is pretty common.
- Dask camera support. This way I could have a much smaller dash camera and be able to view the recordings on the large screen of the head unit and not have to deal with the slow WiFi connection to a phone.
- Bluetooth hands free and stereo streaming. Its amazing how few implement stereo streaming (A2DP). This should be standard. It is getting much better now. A2DP is over 15 years old now and even flip phones had it!
- USB-C Power Delivery. When I am in the car, I often want to charge fast. Most of the head units have very lame USB ports with very little power. If I am going to plug in, I want fast power.
- Integration with the cars controls. If the car has steering wheel or other controls I want that all to work with my new head unit. Most do.
- Integration with the cars existing stereo network. This one I almost never see. My cars have optical audio networks between the head unit, amps, CD changers, etc. You can buy very expensive gateways but it would be great if there was an integrated economical alternative. I want to change the head unit and keep the rest. Its cheaper to just buy a replacement amp right now.
- Remote control knob. I much prefer a control knob like BMW or Mercedes has to a touch screen. I would really like this feature on a replacement head unit. I have never seen this. Many have a remove control but its more like a TV remote than a control knob for a car. I would like this to be a hard wired knob too, not requiring batteries or a wireless connection.
- Remote GPS receiver. Sometimes I just want to see where I am on the map and not have to connect to my phone. You can also get higher quality GPS receivers than what is in the phone.
- Track performance app and related sensors. It would be ideal to have a lap timer, g-force meter, video recorder, etc built in. Ideally I would like to install Harry's Lap Timer in the unit.
I finally narrowed it down to an Android powered system. There are now several available with newer 8-core processors, Android 8, 4GB RAM and 32GB storage. That should give good performance. Here are some I found:
- Pumpkin: https://www.autopumpkin.com/
- Eonon: https://www.eonon.com/ (https://www.eonon.com/Android-Car-GPS/2-Din-GPS-Navigation.html)
- Joying: https://www.joyingauto.com/
There are others. The nice thing about an Android head unit (over just Android Auto) is that you would only need the phone for an internet connection. I can just hotspot my phone and let the head unit connect to it. This fixed item 6 as I would not need to plug the phone into the head unit over USB. Now I don't need my phone for navigation or music. All of that can be handled in the head unit. I can also install both Google Maps and Waze in the head unit and run them from there. These also support backup cameras and even dash camera function. Most have 2 SD card slots and multiple USB ports so storage would not be a problem.