Yes, but only SD versions of movies will play on your iPhone. And if you rent the movie on your iPad, it has to stay on the iPad (don't know why). If you rent the movie on your desktop or iPhone, you can transfer it between devices (but only one 1 device at a time and transfer can be slow). If you buy an HD movie or TV show, they provide both HD and SD copies. You can put the SD copy on your iPhone. I'm not sure but I think if you rent an HD movie then you don't get the SD copy. You can have purchased movies on up to 5 desktop computers authorized with your iTunes account and transfer them to any mobile devices (iPhones, iPods, iPads, or AppleTV's) that sync with those computers.