If you are looking for an App that gives you an anonymous phone number, you may be looking for the Burner App.
Phoneburner does not have an app outside of Salesforce or ZOHO integrations.
This app is not associated with PhoneBurner and is a second phone number app for phones by Ad Hoc Labs.
For Help with this app, please reach out to them directly.
Their support contact is firstname.lastname@example.org