Torify an arbitrary application?

Question

After setting up a self-hosted Nextcloud over tor, I am trying to synchronize an Android Calendar app with it. On Ubuntu I was able to torify vdirsyncer and run khal as a terminal calendar. However, on android I would prefer a GUI, and I have not yet been able to install vdirsyncer in termux.

I tried installing Nextcloud developer app and connecting it directly with the some_onion.onion server, however, as expected that did not work. Hence, I would like to ask:

How can one torify an arbitrary application on Android (using e.g. LineageOS or /e/OS)?

Answer 1

This is exactly what the orbot app does.

To download the app from f-droid one:

1. First installs the f-droid apk from f-droid.org.
2. Next, in that f-droid app on the phone, one can go to: settings> (My Apps)> Repositories> (Enable) Guardian Project Official Releases.
3. (Update the repositories with: `back> Updates> pull the window down to do an update of the repositories).
4. Next, search in the market place search for: orbot and select the one that literally says: Orbot: Tor for Android. If that is not in there, verify you enabled the Guardian Project Official Releases and that you updated the fdroid market place/repositories.
5. Install the Orbot app.
6. Open the Orbot app.
7. Enable "VPN Mode"
8. Select "tor enabled apps" and choose which app you want to go over tor.
9. Back in the main Orbot screen/window, press/hold "start" until you see a green onion.
10. Now you can go to your app, e.g. Nextcloud and enter your https://some_onion.onion domain, to make the Nextcloud connect to your self-hosted Nextcloud server.

This is marvellous work by the Guardian Project I think. I am amazed by how well it works, and have not automated this yet through adb.