I downloaded your sample project and didn't have to change anything other than the startup project to iOS and I could reproduce the problem. Are you sure you ran it on an iOS device? I'm running on an iPhone 6s. It helps if you set EnableLooping = "false". Using the previous and next buttons, the rotator always animates right to left regardless of which button is tapped.
Even if you set the FlowDirection = "LeftToRight" and enable looping, the animation is still right to left. Please take another look at your sample project.