Clickatell
Clickatell is the world's first global mobile messaging company with over 8,000 customers across 600 networks spanning 200 countries. Clickatell allows businesses to connect with their customers and employees in any message format (SMS, E-mail, Voice, Fax, Pager, etc.). Headquartered in Redwood Shores, California the company has offices in the United Kingdom and Cape Town, South Africa.
Clickatell offers customers access to a secure, dependable, high capacity SMS messaging platform. An API is available to allow developers to build their own SMS services using the Clickatell messaging gateway.
At the end of November 2007, Clickatell introduced a new policy whereby only registered numbers could send with a designated "sender" IDs. This only limited the service, and many customers who relied on the capability to set custom sender IDs are moving to the other services.