However, if you are going to take a stand for open computing, you are going to have to make sacrifices. You will have to give up a lot of conveniences. As a technologist you will have to give both time and money. Apple and Google are not going to give up their billion dollar industries voluntarily. You will have to stop giving them money. And you will have to stop using their services.
My solution? I built myself a phone out of a Raspberry Pi 3 with a Touch Screen and a Logitech Headset. It does SMS/MMS and voice only. I've been using it for over a year now as my daily driver.
I'm going to open source the code. Check out https://github.com/another2020githubuser/thepyphone for more details. Right now there is just a README out there, the real code exists in a private git repo. I'm reviewing the code and stripping out private details so I don't end up doxxing myself :)
If you like the idea, please star the github project. I could use the encouragement. Thanks.