Apple except today new iPad and new colorful varianty iPhone to update iTunes. Version 12.6 brings a feature for users called "rent once, watch anywhere". This means that now you can finish watching your rented movie on any device. Previously, if you rented a movie on, for example, iPhone, you were limited to watching only on iPhoneThis new feature requires iOS 10.3 and tvOS 10.2. However iOS 10.3 is in beta (developer and public) and tvOS 10.2 is in beta (developer only), but both updates will likely be available to all users soon.
Source: 9to5Mac