A good mobile alternative to Signal is Simplex, it works both on Android and GNU+Linux. It’s AGPLv3. You have it on F-Droid

I have a Thinkpad X220 myself with Libreboot (coreboot distro). But if you do think that microcode updates is bad you can go for Canoeboot. Always check the chipset in order to know exactly what kind of me_cleaner you have to apply.

Thinkpad X220 works out of the box with Linux-Libre (I use Guix). You probably will need a WiFi card that works with the free software kernel drivers, you can check h-node for hardware that works with free software drivers.

The thing is that that kind of laptops aren’t too powerful. You could check more modern Thinkpads supported at Libreboot.

There are also modern laptops from: System76, framework and Purism. Some support freesoftware more than others, but it’s a good resource. For example not all System 76 laptops have Open Source Bios and EC, most of them disable the ME though.

The phone market is a bit different everything runs on SoC. So unless you go Purism phone or Pinephone. But they lack a lot. I would recommend using a custom de-googled Android like GrapheneOs, CalyxOS or LineageOS.

**Since I’ve been there, take everything with calm. Change bit by bit, and don’t try to force yourself. **

Note: There’s also Briar as a replacement for Signal, but the synching is between devices, so if the other is not connected… I prefer Simplex for now. I really like the way you share chats (since there are no IDs per se). I’ve been testing it out and it works well, you can even call and everything.

Note2: Matrix is a bit shady since the only Matrix instance (public) is Matrix.org and for now their whole selling point is based on that, but we’ll see (I use it too though).