Adobe's mobile apps may be helpful to you. You might want to look at Ai Draw and Ps Sketch. Adobe mobile, iPhone, iPad, Android apps | Adobe Creative Cloud A note your current method: If you have Illustrator, you can bring the scan into Illustrator and use Image Trace to give you a vector trace that you can then take over to Ps. If you don't, you can crisp out the lines and clean up the background by using the levels panel and using the highlight (white) and shadow (black) eyedroppers to increase the contrast. HTH
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