I am in process of upgrading an iPad for testing. I don't see complaints about missing smart playlists on Mac Rumors so I think they will still work.
There are some caveats to smart playlists on devices.
1. The source data has to be on the device for the smart play list to truly work. This means that if you have a smart playlist that has a rule has not been played in the last 2 days and song is not in the Exclusion playlist. The Exclusion playlist has to be on the device. Otherwise the smart playlist becomes static, until it is synced again. This can be worked around using a "source" playlist. For example, if I wanted a car radio of 4 and 5 star songs that are not in the exclusion playlist (audiobooks, podcasts, kids music) then make a Car Radio Source with rules like Stars is greater than 3, not in Exclusion playlist. Then the Car Radio smart playlist has the rules Not Played in the last 2 days, in the Car Radio Source playlist. This allows the Car Radio playlist to be smart, and the Car Radio Source playlist to be static. Usually the Exclusion playlist is too big for the device.
2. Rules usually are evaluated when you leave and enter a smart playlist on a device. iOS never really handled "smart" properly. It only looks at the rules when you enter a smart playlist, so even though you have a not played in the last 2 days rule, the song will stay in the playlist until you change playlists and return to the smart one. Then the played tracks will drop out. They will come back in 3 days if you switch playlists again.