Roku is cracking open access to its Internet set-top device to third-party content providers—adding 10 partners to its “Channel Store” this week—as the company takes a page from Apple’s iPhone App Store. The Roku player, launched in May 2008, initially provided access only to Netflix’s streaming-video service. Since then it has added access to video downloads from Amazon.com (NSDQ: AMZN) and MLB.tv’s out-of-market Internet TV service.

Now Roku is introducing the Channel Store and the 10 new free channels: Blip.tv, Facebook Photos, Flickr, FrameChannel, Mediafly, MobileTribe, Motionbox, Pandora, Revision3 and TWiT. The Channel Store feature allows users to customize which channels they want to see on their menu.

The company in the next six weeks will publish a Web-based software development kit (SDK) for any content provider to create a Roku “channel,” according to director of corporate communications Brian Jaquet. He said there isn’t a fee to add a channel to the Roku service but added that the company reserves the right to approve all channels (the way Apple (NSDQ: AAPL) does for its App Store). More on Mutichannel.