Here’s a nice way to check 32-bit vs. 64 bit application support  (64-bit support is a prerequisite so that an application can be used on iOS 11+)

Solution 1 (on a MacOS environment)

/bin/echo -n "Architecture: "

CFBUNDLEEXECUTABLE=`/usr/libexec/PlistBuddy -c "Print :CFBundleExecutable" Payload/*.app/Info.plist`

xcrun -sdk iphoneos lipo -info Payload/*.app/"${CFBUNDLEEXECUTABLE}" | sed -e 's/^.*are: //' | sed -e 's/^.* is architecture: //'

Solution 2 (on Linux)

Prerequisite: File version 5.25 (at least – check it with file –version command)

unzip myapp.ipa
file Payload/<myapp.app>/app (assuming app is the name of the application bundle in the Application folder)

Solution 3 (manual)

Inspect the Info.plist file and check for the following entry – please note this might not work for old iOS applications

<key>UIRequiredDeviceCapabilities</key>
<array>
<string>armv7</string>
</array>

Meaning of the app architecture for iOS

64-bit: armv7s, arm64
32-bit: armv6, armv7

Note also that on Android there will soon be a requirement for all Google-Play uploaded apps to be 64 bit compatible (in 2019) – see the following article for more information