Tcl cross-platform feature is astonishing. With Androwish [1] it steps even further.
I have a bunch of private tools for personal organization (time tracker, todo list, notepad-like app) that I've written in Tcl. Over the years, I used Android smartphones more and more and I just wanted all those small apps for Android too, but never had time to learn mobile development.
With Androwish I can just run them in my Android almost unmodified! And I can also make use of Android features like notifications. I sync the files between devices with Syncthing [2] or another tool and, voilà! I can use the same apps in both Android and Unix!
EDIT: syntax