Unfortunately, taking pictures of contact information displayed on a computer monitor often doesn't produce good results due to a bundle of reasons. Digital displays have a refresh rate slower than digital cameras can take pictures, so a digital image will most likely include wavy lines or exaggerated pixels which you wouldn't normally see. These visual artifacts add interference to the OCR scan,
Additionally, even though these screens have strong backlights, digital cameras view that light differently, especially with matte style displays, so the lighting condition of these images is really rather poor.
To get around these hurdles you can use the Copied Text feature in the app. By copying the text from an email signature onto your clipboard, you can use the app to then scan the clipboard text for Contact info. Look for the COPIED TEXT option available from the app's home screen.