How 2-way SMS worked ?

2-way SMS 

Virtual Mobile is designed to receive SMS on virtually any mobile network around the world using a standard 11 digit mobile number. 
It has an advantage over short codes, in that like a normal mobile number, it can receive SMS messages from most networks in the world. 
This is completely different to operator short codes, which can only receive messages from users on that network. However, there are no billing options when using a Virtual Mobile number. 

Therefore this is a purely inbound, non-billed solution.

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