How to convert xcode 32 bit app into 64 bit xcode app

Question

I have updated xcode as 6.1 version with ios 8.1.I want to make settings in build settings of project. What changes should be made in architecture and valid architecture of

Answer 1

It's arm64 not armv64

To explain these,

Architectures: First Step is to set the Architecture to Standard architectures (Apple recommended). Which means build both 32 and 64 Bit architectures. This would change your iOS Deployment Target to iOS5.1.1. With a confirmation from you.

Valid Architectures : Specify the architectures you want to build:
armv7 and armv7s are for 32 bit devices.
arm64 is for 64 bit devices

Build Active Architecture Only : This is to specify, whether, build all the valid architectures or build only for the target specified. So for Debug, set is as Yes, hence, it builds only the current architecture, (32 bit, if iPhone 5 64bit if iPhone 5s). And For Release as No. (Build all architecture for Release).

Apple's recommendation on 64 bit conversion

Answer 2

1. Open your app project in Xcode (version 5.0.1 or later).
2. Update the project settings to support iOS version 5.1.1 or later.
3. In the Build Settings section of the project settings set Standard architectures (arm64) for the Architectures
4. The previous changes will raise some compiler warnings and errors in your project.
5. Test the project on 64-bit devices apart from the iOS Simulator.
6. Take advantage of Instruments to check your application’s memory usage.