When iPhone 6 and iPhone 6 plus, the existing apps typically have no promblem running on the large screens. However, they are just scaled and everying looks fuzzy. I personally owned an iOS app in App Store. Becuase I know the bad user experiecne brought by not optimizing the app for the new iPhone(s), I want to update my app as soon as possible.

Then I began to do some research on online to see what I need to do. Surprisingly, I found very few resources teaching you how to do that. So I just want to write how I did that.

0. Download/Install Xcode 6

I feel it’s necessary to mention this step. Xcode 6 includes iOS 8 SDK, which is necessary for iPhone 6/iPhone 6 plus app development. Then use Xcode 6 to open your app. And make you use iOS 8 SDK.

1. Update your launch screens

This step is very important. It’s like a switch. What you need to do is to go to Images.xcassets and create a new Lauch Image. Asides the drag the launch images for 3.5 inches and 5.0 inches, you also need lauch images for 4.7 inches and 5.5 inches. The easily way to create images for those resolutions is to take screenshot on the iOS simulator. Reference

After you do that, congrats! You have turned on the switch! If you run your app on iPhone 6 (or simulator), you should be able to see your app is running without losing any resolution, i.e. not fuzzy anymore. You will probably also see some display issues, e.g. some controls are positioned properly.

2. Build adaptive user interface

The next thing you need to do is to use some techiques provided by Apple to make sure every screen of your app looks good on every iOS device. You can go to Apple’s site to learn more about it. For me, because I’m lasy, I just used Auto Layout to adjust the position of the controls.

What? You’ve done it? Congraluations! You app looks better than 90% of the apps in the App Store. Developers, take some actions, right now!