i was going to call you out for being overly precise, but given that this is literally hosted by essentially a Telecom company its a pretty valid point.

That being said, burner doesn't mean anonymous. Burner means disposable. Obviously you're not going to dispose of your account, application, and server every time you're done with the number.

It's also not even a phone. I guess its a phone application in the most minimal sense of the word..