After trying the new version for a short drive today, probably the most noticeable change in Android Auto 5.3 is the improved performance overall, as everything seems to be more responsive and fluid.
While I never encountered any major bugs with Android Auto, one of the things that I always thought should be improved was how fast the application responded to touch input. Of course, this is also something that depends on the quality of your head unit, but once the action is recorded, Android Auto should respond much faster.
And as it turns out, some improvements have been indeed included in version 5.3. For example, switching between apps – I mostly use Waze and Spotify when driving – is now substantially faster, and on my head unit the difference versus the previous version is easily noticeable.
Another change that I noticed today is that Android Auto starts and closes much faster than on version 5.2. I’m using a Samsung Galaxy Note9 to power Android Auto, it seems this improvement was generated by this recent update, albeit it can very well be the result of Samsung itself refining the experience with some apps.
My Android phone is currently running the April 2020 security patch level.
All in all, even if no major fix or new feature has been included in Android Auto 5.3, it looks like Google is focusing more on refining the experience with the app overall. Of course, as we all learned the hard way, this is something that depends on a lot of factors, including, unfortunately, how lucky you are.