Simple question really. Can I use Atmels
Qtouch library with non-Atmel MCUs (such as an STM32)?
It seems like Atmel has a solid line of capacitive touch ICs, which come coupled with an API library for interfacing with them.
No, because it is not released as source code but as precompiled binary library object. Fortunately ST has a similar touch sensing library you might want to use instead on an STM32.