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It could be actually that this is made with Adobe ;)
We have a team that specialises in Adobe solutions, and one of them made something (with standard controls) that looks like this.
I think Adobe AIR or Flex, don't know, not a specialist in that. NAtive code ftw.
Also like Robbie said, this is fully custom, so I guess, you will have fun with it ;)
Just create a viewcontroller on the left. and a controller on the left, and let the magic happen ;)
 
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