Also don't forget Firefox OS - while I have no idea if or how Mozilla is making any money from it, it is certainly shipping on quite many low-end devices.

An even though I don't really like the app development concept they choose (Javascript & HTML5 only, bleh :P ), the one I got recently due to its low price (~36€) works decently and I could imagine using it as a smarter dum-phone replacement. It has no terminal emulator out of the box and there is no Python and/or Qt/QML, so it is of course totally unusable for serious usage as mobile computer.