We have actually already a good working Continuous Integration (CI) system for the KDE Frameworks (and KDE applications) for Linux thanks to Ben Cooksley. It is based on Jenkins and can be found at build.kde.org.
Some more information about our CI system can be found here:
Is working well.
Some work in progress. Some more information about KDE CI on MacPorts.
A Windows test server is being installed. The current state of getting some free MS Windows licenses is documented here.
Another idea would be CI for and on Android (ARM and/or x86).