I'm having trouble setting exceptions

On my Android phone I use an alternative Anti-Theft app, but Avast is considering it malware. Is there a way to make this app an exception? If so, could someone please explain how I’d navigate to that option? Because I can’t find it for the life of me and I’ve looked around in the forums too with no success. Thank you : )

You can use http://www.avast.com/contact-form.php for reporting potential false positive (archive or site wrong detections).
As far I know, there is no exclusion list.
Is your 3rd party anti-theft tool marked as PUP? If so, you can disable PUPs detection into avast! settings.