Just in: Serial entrepreneur Sky Dayton has stepped down as the CEO of high-end cell phone company Helio, and will become chairman. Wonhee Sull, Helio's president, will become CEO.

I just sat at a dinner with Sky at CES early this month. His enthusiasm for Helio certainly hasn't flagged, and Helio is doing reasonably well. But now that I think about it, even then Dayton was talking about how he likes starting companies a whole lot more than running them. Apparently that's what's behind today's move. Dayton previously started Earthlink, and then Boingo, followed by Helio. No doubt he'd rather spend his time starting something else.

The Helio press statement:

LOS ANGELES, CA - January 28, 2008 - Capping off a year of strong growth, Helio today announced that founding CEO Sky Dayton has been named non-executive Chairman of Helio's Board of Directors, and Wonhee Sull, formerly Helio's President and COO, has been elevated to CEO. The promotions are the culmination of several years' work and will allow both to continue to focus on key initiatives for Helio's success.

"For the past three years, Wonhee and I have worked closely to build Helio, which has seen record growth, introduced over a dozen U.S. industry firsts and established itself in the marketplace as a one-of-a-kind premium mobile service," said Dayton. "Helio has reached a point in its development where I feel the timing is right for this change. I will step into a new role as chairman and Wonhee will become CEO, utilizing his strong operational, product and service experience to manage Helio's day-to-day operations. As we have for the past three years, the two of us will continue to define Helio's direction and future."

Dayton's entrepreneurial history includes a successful track record of starting new technology business ventures as founding CEO, establishing them within their marketplace to a stage where they can proceed toward sustained growth, and after about three years moving to a chairman role where he continues to act as an innovative and experienced leader. Dayton followed similar timelines with EarthLink, which he and his management team grew to a Fortune 1000 company, and more recently with Boingo Wireless, which, under his continued involvement as chairman, has grown by over 1300% and become profitable. Now, after three years, Dayton is handing Helio's day-to-day operational reins over to a proven leader and will remain actively involved in molding its strategy and major initiatives.

"Helio has succeeded where other post-paid MVNOs have not, because of our differentiated message, products and services," said Sull. "We look forward to continuing our growth through the stream of innovation that has defined our place in the wireless market."
Sull was Helio's founding COO, rising to the title of President and COO in April 2006. Sull's leadership at Helio has already included the areas of strategic planning, business operations, products and services, technology and member care. Prior to joining Helio, Sull served as head of the Platform R&D Center at SK Telecom where he had full responsibility for orchestrating and managing numerous commercial services ranging from multimedia to m-commerce, and was instrumental in the growth of SK Telecom's wireless data business.