Hallo
But there is Termux (an Android terminal emulator and Linux environment), its OpenSource,
from Github, with the
Termux Tasker plugin, which can do a lot of things, also symetrical encrytption with e.g. gnupg (pkg install gnupg). This post helped me here:
Termux Tasker works great, I use it already since a while for other things, so lastly I created two tasks to encrypt and decrypt files or folders in the file system with the help of Termux Tasker and gpg (package: gnupg).
First install Termux, better
get the apk from Github (this is the arm64-v8a.apk, maybe you need another version for your architecture of phone) than from F-Droid.
In Termux, install gnupg:
pkg install gnupg
Now import the two attached Tasks. And use them with Action "Perform Task".
The par1 is the path of the file or folder and the par2 is the password.
If par1 is a folder, in EnCryption Task all plain files will be encrypted and in DeCryption all encrytped files in it will be decrypted with the given password (if it matches).
There are some tests for errors, but I am sure there could be much more, so please give me feed-back if someone sees some bugs or glitches (thanks!).
E.g. if there is a password mismatch on decryption, this error is not especially handled, there is only a default error message (containing "...decryption failed: Bad session key").
If any questions, please ask.
In the next two posts, I will put the "Export XML to Clipboard" for the two tasks (EnCryption, DeCryption).
Thanks.frank