Generate a question which can yield the answer mentioned in the input. Generated question must be answered by the answer provided in input, without using any extra knowledge.
Q: Context : CyanogenMod (pronounced /sa.n.o.dn.md/ or sigh-ah-no-gen-mod), usually abbreviated to CM, is an open-source operating system for smartphones and tablet computers, based on the Android mobile platform.
Answer : Android
A:
The CyanogenMod is based upon what?