Matias wasn't involved in PalmOS. Mr. Duarte was involved in Palm's (later HP's) webOS, a distinctly better OS. Prior to that, he worked on Helio phones, by my recollection. He actually carried over his ideas on UI/UX (I struggle to differentiate the two, even though I know it) to webOS and got to implement them from the earliest stages, which is partially how we got the "card" metaphor (later stolen by both Android and subsequently iOS). That basically means webOS was Matias' purest vision; even with Google he's had to work within the existing environment, merely making changes rather than radically redesigning the multitasking or windowing system.
...But I digress. Ed, please change PalmOS to Palm's webOS.