Is there any way of creating a custom renderer that can open word, pdf, rich text, image, etc. files that allows annotations on these and saving the annotated files within a Xamarin.iOS application?
The Syncfusion controls are available for free (commercial applications also) through the community license program if you qualify (less than 1 million US Dollars in revenue). The community license is the full product with no limitations or watermarks.
Note: I work for Syncfusion.
Take a look at Syncfusion's Xamarin Suite.
There aren't any free options out there right?
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