There’s plenty of ways introducing oneself on the phone in German. You already showed one.
Hallo Tante Helga, Michael hier. (Michael here)
Hallo Tante Helga, ich bin’s, Michael. (it’s me, Michael)
Hallo Tante Helga, hier ist (der) Michael. (here’s [the] Michael)
That’s rather colloquial, which was what you asked, right? When calling an unfamiliar person, you’d probably go with one of these:
Guten Tag, Michael Schmidt, …
Michael Schmidt, guten Tag, …
If you’re calling on behalf of your company, you’d name it:
IT-Solutions, Michael Schmidt, guten Tag …
Die Firma IT-Solutions in Musterstadt, Michael Schmidt ist mein Name, guten Tag …
Also note that:
- There’s actually no immediate counterpart for “this is”. You don’t say »es ist Michael« in German.
- This is about introducing oneself when calling somebody. Answering the phone might be different.
- Adding an definite article (to note that the caller is “a particular one which is identifiable to the listener”) is common at least in Southern and Western Germany (like »Hier ist die Michaela«).