Want to send SMS to a mobile phone from your app. Don't have an SMS API that you can use? We can Email to SMS Gateway approach instead. Basically, almost all the telephone carries generally expose an Email to SMS service wherein if you send an email to a specified address with MDN (10 digit Mobile Number) it will, in turn, convert into an SMS and send it to the phone. Doing so does not require any special SMS API but need to program to an API that will send an email with phone no. is all that will be required. There is no cost or authentication required for sending the message as an email,  however, when it goes as an SMS to the phone, the receiver may be charged based on his/her plan with the carrier. Also from a logic perspective in your app, you may have to ask the user their telephone provider or recipient provider in order to pick the right email address to send it to.

Below is a list of email address that various US Telephone Carrier have provided for the same in alphabetical order. Alltel [10 digit Mobile Number]@message.alltel.com Example: 1234567890@message.alltel.com

AT&T (formerly Cingular) [10 digit Mobile Number]@txt.att.net [10 digit Mobile Number]@mms.att.net (MMS) [10 digit Mobile Number]@cingularme.com Example: 1234567890@txt.att.net

Boost Mobile [10 digit Mobile Number]@myboostmobile.com Example: 1234567890@myboostmobile.com

Nextel (now Sprint Nextel) [10-digit telephone number]@messaging.nextel.com Example: 1234567890@messaging.nextel.com

Sprint PCS (now Sprint Nextel) [10 digit Mobile Number]@messaging.sprintpcs.com [10 digit Mobile Number]@pm.sprint.com (MMS) Example: 1234567890@messaging.sprintpcs.com

T-Mobile [10 digit Mobile Number]@tmomail.net Example: 1234567890@tmomail.net

US Cellular [10 digit Mobile Number]email.uscc.net (SMS) [10 digit Mobile Number]@mms.uscc.net (MMS) Example: 1234567890@email.uscc.net

Verizon [10 digit Mobile Number]@vtext.com [10 digit Mobile Number]@vzwpix.com (MMS) Example: 1234567890@vtext.com

Virgin Mobile USA [10 digit Mobile Number]@vmobl.com Example: 1234567890@vmobl.com