Kandroid responds with "server is too old"

When I try to sign in using the Kandroid app I get the error “This server uses a version below 1.0.38. Please upgrade”.

I am running the latest Kanboard Docker (version 1.2.11 ) and Kandroid 0.5.9. Is there a config issue on my side?

Do you have a custom config.php on your data folder?
Check if it’s not setting the version constant with an older value.
Check your kanboard setting page. Which version is shown there?

On the kanboard setting page it shows version 1.2.11. I am not using a custom config.php, I am using the docker image: kanboard/kanboard

I am using a config.php in my data folder, but I don’t see a version constant. If I search for version or VERSION there is nothing there.

I suggest you look into your webserver log files and see if kandroid is making any requests to it and if it’s getting some error.
I don’t know much about kandroid