Products do I use

I believe for this case, you will require both Collections and Disbursements. 

1. Collections/RequestToPay - Get funds from User 1  to your account.
2. Disbursements/Transfer - Transfer funds from your account to User 2

And What Is Remittance?

I want to create an application that can transfer money, that is, 2 users of my application can transfer money to each other.