If you know about mobile email, you certainly know about Research In Motion (RIM) with its over one million users. But did you know that RIM has an up-and-coming competitor with over 200,000 customers?

Like RIM, Redwood Shores, CA based Visto is a company that specializes in mobile e-mail. While RIM owes its success, historically, to a hardware device, Visto's entire existence since 1996 has been as a software platform.

To be fair, RIM has taken to licensing its BlackBerry e-mail and data services to wireless carriers, device manufactures and platform providers, extending the reach of its software beyond BlackBerry handhelds to most other mobile platforms. It even announced a new program, BlackBerry Built-In (see RIM Bolsters Bottom Line by Licensing), the other day to facilitate the process.

Visto has a different business model. Its main focus is on licensing its mobile e-mail platform to wireless carriers, who turn around and sell it to individuals, small businesses and enterprise customers under their own brand name.

As with RIM's BlackBerry platform, Visto software pushes e-mail, contacts and appointments to mobile devices-- PDAs, smartphones, or mail phones that support WAP and HTML.

Currently, nine operators offer Visto-based e-mail to subscribers in North America, Europe and Asia. These include AT&T Wireless, KPN, Nextel, SmarTone, MTS, Bell Mobility, Rogers Wireless, SaskTel Mobility, and Telus Mobility. The company plans to announce more carriers later this year.

As of June, there were over 200,000 Visto e-mail users out there. That's a jump from 100,000 in February, and a lot of customers for a company that remains for the most part anonymous.

Visto views itself as a leader in a trend towards bringing mobile e-mail to the masses.

According to Visto's Chairman & CEO Brian Bogosian, "the heart of our proposition is that with the Visto Mobile platform, wireless operators can offer customers individual, POP3, or corporate email/PIM accounts. What's more, they can use handsets from Sony Ericsson, Nokia, PalmOne, or many others, and run the service over Windows Mobile, Symbian OS, PalmSource, or J2ME operating platforms. Our proven track record of delivering these solutions to 200,000 customers across 9 carriers makes us the one to watch."