Not a support question, but wanted to make sure what I found was easy for others to find if they have the same problem. After spending a lot of time trying to figure out why my touch events stopped working on iOS after I upgraded from Urho3D 1.5 to Urho3D 1.8 alpha, I found out that is was related to my code being setup to run on both desktop and touch platforms. Apparently in SDL2.0.4, iOS (and presumably Android), generate mouse messages for touch events by default (I don’t think that was true in the earlier version of SDL that Urho3D 1.5 used). In my application, I run the same code on Windows and iOS, so I had both mouse and touch event handlers, and they started both getting called on iOS, which caused a lot of bad behavior. I found this link that talks about the problem.
So for me, the fix was to call the following in my initialization code. Even though the hint appears to be specific to Android, it fixed my problem on iOS as well.
//In initialization code