The Multipeer Connectivity APIs, introduced by Apple in iOS 7 is an easy way to start building apps requiring peer-to-peer communication. Nearby devices communicate over infrastructure Wi-Fi networks, peer-to-peer Wi-Fi, and Bluetooth personal area networks. Connected peers are able securely transmit messages, streams, or file resources to other devices.
Evaluation of different aspects of Multipeer Connectivity with iPad Air 2 devices shows surprising results. Discovery and communication between iPad devices works mostly well. However, some shortcomings are to be mentioned here.
- Establishing connection between peers always requires user interaction. The user has to confirm a connection to other device. There is no way to work with certificates or white lists of devices.
- The other issue is that the framework does not always repair the broken ad-hoc network correctly. If a peer suddenly leaves the network, it often stays broken. Discovery must be restarted manually.
- Multipeer Connectivity framework is only available for iOS, macOS and tvOS devices. So if the app has to run also on Android or Windows devices, this framework cannot be used.