By flash back do you mean the Pdf Screen just closes and you go back to the previous screen? App doesn't crash? Does it behave exactly the same as if you were to just click Back button? When you say 'after using a stylus' do you mean you are able to draw a few annotations and then when you try drawing a next one it just flashes? Or you can only draw very little part of the first annotation and it flashes mid-draw? Or you can't even draw a single one - does it flashes the moment you as much as just touch a screen with a stylus? Also does creating lots of annotations with you finger work just fine?
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When you say 'after using a stylus' do you mean you are able to draw a few annotations and then when you try drawing a next one it just flashes? Or you can only draw very little part of the first annotation and it flashes mid-draw? Or you can't even draw a single one - does it flashes the moment you as much as just touch a screen with a stylus?
Also does creating lots of annotations with you finger work just fine?