Writing stable iOS applications

AltConf 2019 in San Jose
June 5, 2019
http://altconf.com/

Breaker is the #1 social podcast app for iOS, funded by Y Combinator, and used by thousands every day. In order to be reliable, Breaker needs to minimize bugs and prevent crashes. Find out how we create a stable app, using tools to monitor crashes and errors. We’ll also explore how testing and debugging work in iOS and how to utilize user feedback to improve app performance.

Transcript

1. Leah Culver - Breaker
 AltConf 2019 Writing stable iOS applications
2. Me Developer for 13 years 3x startup founder
4. • Find and follow friends • Share on Twitter, Facebook,
 Instagram, and Snapchat • Send episodes to friends and chat • Like episodes ❤ • Comment on episodes • Find new episodes
 based on likes, listens, and comments Breaker
5. One of the top podcast apps for iOS (Android coming soon!)
6. Launched 2 years ago - all Swift!
7. Crashes!
8. Why do we care about crashes?
9. jarring experience feels wrong broken!
10. What’s the alternative? Doesn’t quite work.
11. Common crashes
12. Force unwrapping optionals
13. let url = URL(string: "https://www.breaker.audio")! Simple example
14. let url = URL(string: "")! Simple example
16. Why? • Code refactor • Copy/pasted code • User-entered values • Something weird happened!
17. If-let if let url = URL(string: "https://www.breaker.audio") { print(url.absoluteString) }
18. Guard guard let url = URL(string: "https://www.breaker.audio") else { return } // Everything is chill. print(url.absoluteString)
19. Nil-coalescing let url: URL? = URL(string: "https://www.breaker.audio") print(url?.absoluteString ?? "No URL found.")
20. Just don’t do it!
21. @IBOutlet weak var titleLabel: UILabel? titleLabel?.text = show.name We’re hardcore.
22. Array index out of bounds
23. Simple example
24. Easy fix!
25. Easy fix!
26. Safe!
27. Misconfigured IBOutlets
28. Eek.
29. @IBOutlet weak var showNameLabel: UILabel? Renaming
30. Refactor
31. Refactor
32. Try out views?
33. UI updated
 on a background thread
34. Example Push notifications
35. Example
36. Easy fix!
37. Tools
38. Crash logging
39. Stack trace
40. Line 479
41. Safe!
42. Exception logging Don’t crash - just log it for later!
43. Exception logging
44. Exception logging
45. Tools?
46. 1. Look for common crashes 2. Crash and exception logging What?
47. Thanks! Download Breaker. We’re hiring! https://www.breaker.audio
48. Photo credits https://www.flickr.com/photos/marian_e_may/24355452028 https://www.flickr.com/photos/ayesham/23746683041 https://www.flickr.com/photos/dubwise_version/4718137117 https://www.flickr.com/photos/esperbot/41779302514 https://www.flickr.com/photos/stewdean/9782073011 https://www.flickr.com/photos/speedoflife/8345885557 https://www.flickr.com/photos/sanspeur/2420943099 https://www.flickr.com/photos/lash9420/7112309139 https://www.flickr.com/photos/avidlyabide/6545946991 https://www.flickr.com/photos/linvoyage/14463878257 https://www.flickr.com/photos/sk8geek/3438835775 https://www.flickr.com/photos/swisscan/2514879116 https://www.flickr.com/photos/w4yn3drb/7081697671