Newbie, not sure where to start

Hello,

First of all, I want to say I am new to this. Please forgive my ignorance…

What I want to do is have an application automatically connect to separate phones together and meter their usage. Perhaps this would be 3 callers in total. The system is a caller, calls person A then calls person B so person A and B can interact. I need to meter/time how many seconds their call is going. The only issue I have is understanding how to implement such a thing. I am a developer but I am not sure if there are third party programs that do this or modules. Or, if a customization is warranted, where would I start?

Any information is appreciated!!

Thank you!