The iOS Simulator is very powerful and allows for doing most of the testing you need for most business apps. In a classroom situation you can do a lot of interesting and worthwhile things without using real devices. However, students get excited about seeing their creations running on a real device, and there are certain features where it is necessary to test on a device. Following are some limitations of the simulator where you need to test on a real device:
No phone or messaging. The Simulator can toggle the in-call status bar, but doesn’t make or receive calls.
Access to camera.
Realistic access to network ...