HTC patents a dual-screen slider phone that you likely won't see
 

While HTC is certainly willing to accommodate multiple screen sizes and form factors with its phones, we suspect that some of its explorations won't go beyond the lab. If you'd like an example, see the company's newly obtained patent for a dual-screen slider design. Oh, it's clever: the mechanism gracefully moves a hidden second screen into place, tilting the unfolded arrangement to form one united display area. Like with other dual-screen patents, we're skeptical simply because of market realities. HTC's rocky financial position doesn't give it much room to take risks, and dual-screen phones need special software support that often makes them non-starters -- just ask any Kyocera Echo owner how that developer program is panning out. As a result, it may be more accurate to call the patent a vision of what might have been than any kind of roadmap.

http://www.engadget.com/2013/04/16/h...%28Engadget%29