You are not far from the reality.
Basicaly QNX was the operating systems of Blackberry phones and mainly used in many embadded systems. For example this days is the most powerfull and mostly used operating systems in car navigations and instrument clusters (just some examples: VAG - RMC, MMI3G, MIB1/2/2p, BMW, Mercedes, uConnect (Fiat, Crylser, LR), Ford Sync3 and so on).
QNX is an UNIX based operating system with microkernel (there are very few microkernel based OS). Some of its components are adopted from NetBSD (for example the network stack) for this reason QNX is mostly compared against NetBSD.
It's a very power full OS, supports to work in multuple nodes where clusters communicates on QNET.
Just an example how pwoerfull is the QNX:
In case of VAG MIB1/2 navigations there are 2 subsystems (2 nodes) in the nvaigation unit: RCC and MMX. RMC executes the the low level functions including security checks of the navigations (like feature codes, component protection) and MMX runs the user enviroment (like the GUI). For example the sdcard are available only from MMX (user environment) and not from the low level RCC node. The 2 nodes are communicating on QNET. So the user accessable area and the low level functions are separated on 2 nodes....
I thinks this days the QNX is the most powerfull embaded operating systems...