Yeah I'd be curious what both your and parent's use cases are that could possibly be covered by other smaller, existing maps services, or if there is some market that remains underserved.
We build a service calculating those but have trouble getting the data.
It is more of a nice gimmick for us. Since the pricing changes using Google maps apis is just prohibitively expensive.
There are other companies providing the data but those too are somewhat costly.
Maybe we should use open street map as a data source.