Free SMS Gateway lets users send text messages to groups of people through either a web interface or a RESTful API. Users can import their contacts via text list, CSV file, or by hand. They can also view past messages, sent dates, billing statements, and more. Free SMS Gateway starts users out with a free account which they may choose to upgrade or cancel at any time.
The following is a list of SDKs from our SDK directory that matched your search term. Though your definition of an SDK may differ, in our world, we define SDKs as platform- specific tools for consuming existing APIs of the sort we list in our API directory. For example, the Ruby SDK for consuming the Twitter Ads API. If you think an SDK, API, or other asset is missing from our directory, be sure to check our guidelines for making contributions to ProgrammableWeb.