PHP Point Of Sale now integrates with Twilio for sending SMS messages and receipts to customers.
To enable this you must for signup with Twilio
Once you have signed up you would need to enable your account to send SMS. Once signed up Twillio will provide a phone number, SID, and Auth Token.
This information would be entered into PHP Point Of Sale --> Locations --> Edit
Once this information is put into PHP POS you are ready to start using SMS!
To create a message to send to one or more customers navigate to the customer's module and check the box(es) next to the customer(s) you want to send a message. Then click the Send SMS and type your message
If you want to SMS receipts you would simply check the Send SMS button next to a customer that has a phone number during the sale.