Send sms from PC connected to a smartphone

Question

Hello everyone

 

I am making a project for a cafe in which the client wants to send SMS to their customers.

 

How can I used to connect a smartphone to PC and send SMS to the customer which is connected through USB cable.

 

I searched on Google, they are sending using com port, I tried some sample program but no luck

 

Can someone guide me for the same?

 

Thanks

Devendra