Multipeer connectivity is something that used to be awfully hard, but in iOS it's less than 150 lines of code to produce this entire app – and over half of that is code for the collection view and the image picker!
The advantage it has compared to traditional data sharing over Wi-Fi is that multipeer can use an existing Wi-Fi network, or can silently create a new Wi-Fi network or even a Bluetooth network depending on what's available. All this is an implementation detail that Apple solves on your behalf.
If you'd like to take this project further, add a button that will show a table view listing the names of all devices currently connected to the session. You could also try sending text messages across the wire – there's a
data(using:) method for strings that converts a string to
Data. Use it with the parameters
String.Encoding.utf8 to ensure everything is sent safely.
One of the most effective motivators of success is sharing your progress with other people – when you tell folks what you're doing and what you've learned, it encourages you to come back for more, which in turn will help you reach your app development goals faster.
So, now that you've done all the hard work it's time to share your success: tell folks that you've completed this project, either by clicking the button below to start composing a tweet, or by writing your own message from scratch. This will definitely encourage you to keep learning, but it will also help other folks discover my work – thank you!
Paul Hudson is the creator of Hacking with Swift, the most comprehensive series of Swift books in the world. He's also the editor of Swift Developer News, the maintainer of the Swift Knowledge Base, and Mario Kart world champion. OK, so that last part isn't true. If you're curious you can learn more here.