How do I import a PDF that's on my device or SD card?
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To show the device storage and any external storage, tap the three dots in the upper right corner:
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Then tap "Show internal storage" (or similar; your device may show something different):
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Then tap the three horizontal lines in the upper left corner to open the drawer again:
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You will now be able to select the internal device storage as well as any external storage such as an SD card or USB drive that is attached:
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