leedumond.com — There are lots of commercial services that provide convenient APIs to SMS gateways. The problem is, they all cost money. Most charge a monthly service fee, plus a fee for each message – often as high as 20 cents per message for casual users.
However, if you need to send SMS messages to the US and Canada, you can take advantage of the Email-to-Text capability provided by most mobile carriers, which is totally free.
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