GoKawiilThe convenience of being able to install all sorts of apps Google hasn't intended comes with some genuine drawbacks that you should take seriously.
Safety is a major concern. Android Auto YouTube is technically an option even through official channels, but you can only listen to the audio. There's a reason Google hasn't allowed YouTube videos on Android Auto by now and that's because watching videos while driving is not a good idea. In fact, it's illegal in most parts of the world. This is a feature that should only be used when parked.
Malware exposure. Any time you sideload apps and skip Google's security screening, you open your devices to the risk of malware. Google reports that internet-sideloaded sources carry more than 50 times more malware than apps on Google Play. That's one of the reasons why Google will start blocking the sideloading of unverified Android apps, asking developers to verify their identity with the company. These new verification requirements will begin rolling out in late 2026 in a few countries before going global.
For most drivers, the standard Android Auto experience covers everything they actually need. Sideloading is a great capability, but for the vast majority of people, it's best left as a curiosity rather than a daily-use setup. If you do proceed, download only from trusted developers and only use video features when parked.