When I use the Xcode 8 beta(8S128d) to open my project,it recommend me to change the min iOS Deployment Target to 8.0 instead 7.1. And I found that there is no option less than 8.0 in the iOS Deployment Target list.
So, does it mean that I no longer need to adjust my project for iOS 7.x or less?
If you don't want to fiddle with XCode just update your project file for iOS 6 or 7.
Right click .xcodeproj choose "Show package contents" and edit project.pbxproj in favorite text editor.
Search for IPHONEOS_DEPLOYMENT_TARGET = 7.0;
I think if the app has many users who are using iOS 7, it would be necessary to adjust project to support iOS 7.
I have tried build, debug, archive with deployment target 7.0 using Xcode 8 Beta(8S128d).
All succeeded. Also successfully export and install the ipa on my iPhone 4 (iOS 7.1.2(11D257)) .
I did the followings to change my project deployment target to 7.0 and remove the suggestion warning.
Manually input "7.0" in the "iOS Deployment Target" text box.
Uncheck the "Update iOS Deployment Target" and press "Perform Changes" / "Done" button,
then the recommended suggestion warning will disappear.
Edit:
Make Xcode 8.x debug your apps on iOS 7.x devices.
You need Xcode 7.x . You can download it from Apple Developer Site.
Open Finder, and go to "Xcode 7.x.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/".
Copy "7.0" and "7.1" folders and paste them to "Xcode 8.x.app/Contents/Developer/Platforms/iPhoneOS.platform/DeviceSupport/".
Restart Xcode 8.x.
Now you can choose "7.0" or "7.1" in the "iOS Deployment Target" text box list and debug your apps on iOS 7.x devices.
The minimum deployment target with Xcode 8 is iOS 8. To support target the iOS SDK 7.x and below, use Xcode 7.
If you try to use a deployment target of iOS 7.x or below, Xcode will suggest you change your target to iOS 8:
Apple has changed so much since iOS 7 until now. The easiest way of not having to deal with backward compatibility is to make the old OS's obsolete.
So you have 2 choices. You can leave the setting as is and deal with the warning message,or you can change the setting and not support iOS 7 or lower any longer. There are pros and cons to each...Leave the setting: If you chose to leave the Min OS setting as is your app will have a larger user base. But since new OS adoption rate is very very high this is not as much of an issue with iOS devices as it would be with Android devices. You would also have to deal with supporting iOS 7. That means that if you decide to use any new features not available in iOS 7 you would have to deal with the iOS 7 case. Possible app crashes, inconsistent UI, etc...Change the setting: If you chose to change the setting then you no longer have to support iOS 7 (you can create much simpler and more consistent code with new features). You also slightly shrink your customer base (very very slightly).
It's up to you what you would like to do, but really all devices that can run 7 can also run 8. So if they want your app they can just upgrade OS's and be fine (not like the iPad 1 that stopped at iOS 5). My customers are all large businesses that need to run through lots of red tape to upgrade their fleet of devices. So I have to support iOS 7 (for now, xCode 8 may give me the sway to force those who haven't to upgrade).