Palm acquired the rights to BeOS, some part of it was used as the guts of webOS for their run at the new-wave smartphone market, and then that of course was acquired by LG, which then used webOS to power some number of smart TVs. If I'm remembering correctly.
Funny, then, that even BeOS or a sliver of it lived on in a mobile operating system. See this conversation about how Linux seems to almost overwhelmingly dominate the mobile OS space, with iOS as the most significant exception.