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If you use a phone to take a picture of your work, use a scanning app and not just the camera. The Google Drive app (iOS and Android) has a built-in scanning tool as does the Notes app (iOS only). Most professors prefer that you combine multiple pages into a single PDF file. Double check the page size the app generates to make sure it is 8.5”x11”.
Other popular options are Scanner Pro, Genius Scan, and Adobe Scan.
Format
When scanning, select the Color option. The Black and White setting does not show up well. Greyscale may work, but Color is better for clarity, especially for lined or graph paper. Select PDF as the output format. Make sure the page size of the output is standard letter size.
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