Update Xcode 10.1 to 10.2 on High Sierra 10.13.6

Follow these steps:

1. Download Xcode 10.2 via this link (you need to be signed in with your Apple Id): https://developer.apple.com/services-account/download?path=/Developer_Tools/Xcode_10.2/Xcode_10.2.xip and install it
2. Edit Xcode.app/Contents/Info.plist and change the Minimum System Version to 10.13.6
3. Do the same for Xcode.app/Contents/Developer/Applications/Simulator.app/Contents/Info.plist (might require a restart of Xcode and/or Mac OS to make it open the simulator on run)
4. Replace Xcode.app/Contents/Developer/usr/bin/xcodebuild with one from 10.1

I am using Xcode10.2 on High Sierra 10.13.6, and can build several projects for my iPhone 5s and 6s Plus which working on iOS12.2. The process is similar to Damnum’s.

1. Change the name of working Xcode like Xcode10.1.
2. Download Xcode 10.2 and copy it into Applications folder. (The name is of course Xcode.)
3. Edit Xcode.app/Contents/Info.plist and change the Minimum System Version to 10.13.6 with Xcode10.1
4. Edit Xcode.app/Contents/Applications/FileMerge/Contents/Info.plist and change the Minimum System Version to 10.13.6 with Xcode10.1
5. Edit Xcode.app/Contents/Developer/Applications/Simulator.app/Contents/Info.plist and change the Minimum System Version to 10.13 with Xcode10.1
6. Launch Xcode (it is 10.2) and install the rest of items.
7. Now you can use iOS12.2 features in the Xcode.

I tested my own projects and several sample projects from iOS 12 App Development Essentials by Neil Smyth. All of them work fine on my devises including camera app.