If you are a developer of window based software and wants to add SMS and MMS facility to your software then you can use ActiveXperts SMS and MMS Toolkit for the same. You can also directly use this toolkit to send and receive SMS and MMS. It is also able to deliver ringtones, pictures and WAP etc. To deliver your messages or content it gives you a wide variety of options for full flexibility. So you can choose any of them from GSM modem, GSM phone, SMPP compliant SMSC provider, HTTP compliant SMSC provider or Hayes compatible modem to send SMS. To send MMS it also support MM1 (GPRS), MM4 (SMTP) and MM7 provider (XML/SOAP). I forget to tell you that sending a pager message is also possible via SNPP by using SMS and MMS Toolkit.