On the early alkaline / NiCd AA battery powered WinCE PDAs with as little as 2-4 MB of RAM and a very slow single core processor, having only 32 process slots wasn't really a limitation. You couldn't afford too many processes or to be doing much computation anyway.

Don't get me wrong by the way. For their time, the early PDAs were expensive, bleeding edge tech and the limited things that could be done with them was still unprecedented. They crawled so future smartphones could run.

WinCE had a load of weird issues (and looked consistently awful), but moving onto PDAs and even phones running it from a world of Psion and Palm was like stepping forward a century. This might be rose tinted recollections - and helps that it coincided with with the consumerisation of WiFi and Bluetooth - but fond memories. I still can't believe how Microsoft had a surprisingly capable mobile OS years before Android or Apple and yet managed to fail so badly.

Windows CE late in its lifetime (CE 6.0) had that go away with per-process address spaces.