Yam Display Alternatives
Yam Display is described as 'turns your iPad or iPhone into an external display for your Mac via USB'. There are five alternatives to Yam Display for a variety of platforms, including Mac, iPhone, iPad, Windows and Android Tablet. The best alternative is Duet Display. It's not free, so if you're looking for a free alternative, you could try Deskreen. Other great apps like Yam Display are iDisplay (Paid), Air Display (Paid) and Displaypad (Paid).