Currently, Arti on mobile is still quite experimental and not actively maintained.
The features it already has can be tried out on iOS with either using Arti Mobile Experimental directly, or by using it embedded in Tor.framework, which gives you the advantage of having some helper classes at hand.
There's a Podspec, which supports that.
In your Podfile:
pod 'Tor/Arti', :podspec => 'https://github.com/iCepa/Tor.framework/blob/pure_pod/Arti.podspec'Said Podspec also contains an experimental version of OnionMasq, which contains Arti + IP packet routing (so you can use it on a tun device or Apple's Network Extension API directly).
At some point in the future this will probably replace the C-Tor + IPtProxy + leaf combination, which Orbot iOS currently uses.