Is it possible to make payments between two clients from an app?

I just want to know whether we can write an app that acts as a third party in a bank transaction between two clients.What my main motto is to facilitate a user to pay some amount to other user from my app.So i want to know whether we can do this or not? Please give me any kind of suggestions…
P.S. I am new to this forum. So please help me.

You mean you want to make an app for a bank ?

Anything is possible (given enough time+money!)