Luca is basically meant as an addition to the bluetooth based tracing app, there were competitors but kind of because of political favorism this provider had been preferred - even though better alternatives were also open to be picked. The owners made quite some significant money by contracting with different state/city governments.
Note as on previous posting of this app.
> This is not the official contract tracing app (that one can be found here https://github.com/corona-warn-app), its a commercial product
https://news.ycombinator.com/item?id=26644246