It's not enough for everyone on earth to have a single mobile phone—Real Networks CEO Rob Glaser thinks that everyone will eventually have at least two. Glaser spoke at this week's Mobile World Congress Conference in Barcelona, insisting that it wasn't possible for a "do everything, no compromise" device to exist and serve people's every mobile need.

Glaser explained that his belief was fueled by differences in input methods, size, and functionality between devices. No single phone can do everything easily, he said, which is why the public will be driven to carry multiple devices. "Mobile penetration won't stop at 100 percent," he told the crowd. "It will go to 200 percent because the notion of a single device that does it all isn't the way (the market is) going to go."

Do most people really need two phones? Yes, the mobile landscape isn't perfect, even with the continued introduction of increasingly capable devices. And it's true that there are some people who do already carry around more than one mobile device because they need different functionalities from each one, but those people are still a minority. The general public (at least in the US) is still just getting up to speed with the concept of a smartphone that can do more than just make and receive phone calls—give your average Joe an iPhone or a BlackBerry Pearl and he'll be beyond satisfied for a long time to come.

Arguably, mobile customers' willingness to embrace devices that can't quite do everything they want leads them go purchase multiple devices in the first place. Manufacturers (and the carriers who love them) are still falling short on the user experience front, as evidenced by another panel held at Mobile World Congress. Called "It's the User Experience, Stupid," the panel cited recent survey results that showed exceptional user satisfaction with the newly-launched iPhone, and pointed out that the industry could benefit from emulating that experience elsewhere. Panelists agreed that user experience with other devices has not been very good—data prices, content, and ease-of-use are major hurdles that need to be overcome.

No one wants to carry around more stuff than they need to; instead we do it out of necessity because the situation is still so unsatisfactory. (For example, Jon Stokes proudly declared last September that he carried around three separate mobile devices. He has since become an iPhone user even though he still has plenty of room in his manpurse.) If the mobile industry does a better job of creating capable devices, easy-to-use software, and understandable (and affordable) data plans, Glaser's prediction is unlikely to come to fruition.

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