When you enter Google Play or App Store link in "Application URL" field while setup campaign then the platform will automatically validate the app and shows it's details but in case it does NOT happen then you can hit "Validate" button to force the validation process.
Note: Our system validates app in US market so, if your app is NOT available in US then you may get validation error.
Still Getting Validation Error?
In case you are still getting validation error even after hitting "Validate" button then you may make use of "Skip Validation" checkbox to skip the same in such rare cases.
Note: Use "Skip Validation" button only if you believe that your app is live in the Play Store (or App Store)
Advanced Solution for some Rare Cases:
In some rare cases it can be possible that the app is available only in one or two country then please first choose your target country before validating your app. System will validate your app against the very first country shown in the targeted country list after selected.