Find out iOS SDK version from IPA

Recently I updated xcode on our CI server and additionally provide the option to use older xcode versions per project.
To verify that the option works I wanted to find out the iOS SDK version from the provided ipa.

Here we go:
Assuming the app is named APPNAME and the ipa my-app.ipa.

  1. rename my-app.ipa to my-app.ipa.zip
  2. unzip my-app.ipa.zip (Now we’ve got a folder named Payload)
  3. execute the following bash command:
    otool -l Payload/APPNAME.app/APPNAME | fgrep --after-context=3 LC_VERSION_MIN_IPHONEOS
  4. (Alternative)
    plutil -p Payload/APPNAME.app/Info.plist | grep DTSDKName

The output is something similar to:

cmd LC_VERSION_MIN_IPHONEOS
cmdsize 16
version 7.0
sdk 8.4
--
cmd LC_VERSION_MIN_IPHONEOS
cmdsize 16
version 7.0
sdk 8.4