Hi @gubatron,
Thanks for reaching out!
You are correct that some of the click URLs for our ads open in the device’s browser (ex: Safari or Chrome), some open in the MoPub native browser and some open in the App Store or Play Store. Where click URLs open is determined on the creative level by the advertiser / creative vendor.
If this seems to be a one-off issue affecting one or more ads from the same advertiser, you can feel free to escalate the ads to us via our Creative Flagging Tool. That way, we can review the creative and block it if it is broken. Please make sure to include a summary of the problem in the email generated by the creative review tool and send it to our Support Team at support@mopub.com.
If you believe this to be a larger integration issue, we’d recommend testing your ad units in the MoPub Sample App to see if you can replicate the problem. If you can’t replicate the problem, reviewing our Sample App integration is a good place to start to see what might have gone wrong in your own integration. You can always feel free to reach out to our Support Team at support@mopub.com for additional assistance.
Thanks!