For how much would you port Delta.chat to ARM / Raspberry Pi?

I assume you’re talking about deltachat-desktop? You can actually get that for ARM right now, even though there is no official Flatpak or AppImage. If you’re running a 64-bit version of Raspbian and don’t want to compile things yourself (which might not even be possible on weak ARM devices), you can e.g. get it with the Nix package manager:

  • Install Nix as described here. That script will modify ~/.profile and print instructions for updating your $PATH in case you don’t want to log out and log in again.
  • Install deltachat-desktop using nix-env -f '<nixpkgs>' -iA deltachat-desktop. You should now have deltachat in your $PATH and hopefully in your launcher.
  • Keep it up to date using nix-channel --update && nix-env -u --always.

You can also install KDeltaChat (-iA kdeltachat) and Cursed Delta (-iA deltachat-cursed) that way.