Chances are pretty good that you, like me, spend more than a small amount of time in front of a whiteboard. Whiteboards are, after all, pretty great; if there's a better way to facilitate group-think sessions where outcomes are determined through collaboration, I can't think of it.
But. They have a problem. The content you put on them - unless you hog whiteboard space - can only remain there temporarily. In fact, in many circumstances, you're going to need to nix it pretty much immediately so that the people waiting outside can use the space for their discussion.
So what to do?
The obvious answer is "take a picture" and that's a solution that works - I'm not suggesting it doesn't. What I am suggesting, however, is that it's possible to take a picture using a tool that's specifically designed for the task (taking pictures of whiteboards) rather than generally suitable.
That tool is called Office Lens. Made by Microsoft, it's an app available for Windows Phone, iOS, and Android that is contextually aware of the task (taking pictures of whiteboards) with tools that make it more effective than just using your normal camera app.
Specifically, it will identify the shape of the whiteboard you're snapping and straighten it up when you take the photo - effectively letting you take pictures from any angle and still generating an image as if you were straight on. It also reduces glare and crops out non-whiteboard parts of the image, resulting in a useful record of your meeting that doesn't look silly and won't need any further editing after the fact.
Images from the App Store listing, hilariously featuring decidedly non-Agile project planning
Neat!
It also works well as a document scanner, making it a great device for adding pictures of receipts to Evernote for later expense tracking (etc).
All in all, for a free app it's pretty great. I suspect it would be even better if you're closely integrated into the Microsoft ecosystem, thanks to its built-in ability to save to OneDrive, but that's not something I've personally ever needed to take advantage of (you can, of course, save it to the local device for utilization however you like!).