I need a free SMS script for website
I have a website where I give different services to my users.
It contains different topics that the users can freely share their views and other comments to it.
For the next year I want to upgrade the communications even better, having new ideas, one of which in having a free sms where users can send text message through the site.
I need to know if there is a free sms script for website, or was the cheapest but efficient tool available out there.