Web: You can avoid taking notes during a meeting by simply taking a photo of the whiteboard at the end. But those photos might not be perfectly legible. Unwhiteboard is an email-based service that cleans them up
Simply send your email to this address:
Note that Unwhiteboard won't transcribe your whiteboard. It plays around with the image settings so that the ink has a higher contrast against the white background. The end result is that you can read it more easily.
The app takes a few minutes depending on the size of your photo, but you will eventually receive a more legible version of the image in PDF form.
This is a much easier option than doing those image edits yourself, especially since you don't need any software or app installed. Just one email and you're done.