Things to be considered while upgrading the iOS app

Question

There is an iOS app developed in iOS 4.3. Now I want to upgrade this app to iOS 9 and later. I can able to run the application even on iOS 10 devices. But there are lot of deprecated warnings regarding the latest SDK.

The main reason I'm posting this question is, while upgrading the app from lower version to latest version, what are the action items to be consider to make the application perfect on latest SDK?

Here are few points I've noted,

1. Clear all deprecated warning.
2. Do analyser for memory leak.
3. Enable ARC if not enabled yet.
4. Proper unit testing.

Please advice me some more point.

Note: I'm not converting the app to Swift, using Objective-C only.

Update: I know the basic things like changing the deployment targets, update the used libraries / Frameworks to latest one, etc., I want more high level points those features are available in latest SDK comparing with lower one.

Thanks

Answer 1

Here are some more points you have to consider for latest iOS support,

1. Change deployment target in general setting.
2. Check for device compatibility for design constraint. There are new devices.
3. Change the version of your app in general settings.
4. If there are any functionality for touch event than check if it is possible to implement 3D touch for newer device.

And go for proper testing of functionality and design.

Hope it will help you.