A simple thing you can do is be informed on what data google is tracking on your phone.
If you are signed into a Google account on your phone, you should check your Google dashboard: myaccount.google.com/intro/dashboard and make sure to turn off any tracking you don’t want. You can also request your data is deleted through the dashboard or through Google takeout.
If you stay with the built in OS and you can also get away from a Google account (don’t sign into a Google account on the phone), you’re tracked less, but that’s a bit challenging for many.