Better is only a matter of perspective. I have an 4s and a friend has a NexusS, I can tell you that we can almost do the same things almost the same way.
Once you install all the applications you need, you stop fiddling and stability is good, at least for my friend.
iOS might be more "stable", but that is only because we can't install anything that has system rights. Just try to stop Bluetooth, Wifi or 3g Data without going 5 levels deep in Settings. Cripple Android the same way iOS is and I assure you that is is just as stable.
I like my 4s but some applications are available only on Cydia, and at the moment I don't want to go there. Maybe all those running wild (jailbreak) can comment on stability.