flutter real-time phone number access

Job ID: 33194949

Budget: $60 – $100 USD

A call comes from the number xxx-xxx-xx-xx over the GSM operator.
An incoming call is detected by a service waiting for an incoming call in the background.
sends a request to query the incoming call number via an api.
shows the incoming answer on the call answering screen.
the person answers the call or presses the busy key.

It will be a Flutter-enabled iOS app. android optional.