outstanding idea...it saves the trouble of creating and renaming bookmarks manually after merging several files. I ran into this several times. Would be nice to make an outline with the names of the former PDF files and of course implement the original outlines.
in addition it would be helpful to be able to filter or group different icon shapes i.e. have all question marks or all exclamations or text balloons selected separately.
Thanks for your awesome feedback! Defining exact hex color value, entering exact thickness/opacity/text size value is now available in Xodo beta! See http://feedback.xodo.com/knowledgebase/articles/1119511-change-style-of-an-annotation-color-thickness-o.
To enter exact color HEX value, see: http://feedback.xodo.com/knowledgebase/articles/1849546-annotation-color-picker.
To define and select style presets, see: http://feedback.xodo.com/knowledgebase/articles/1851553-setting-an-annotation-style-preset
You can become our beta tester as described here: http://feedback.xodo.com/knowledgebase/articles/829551-becoming-a-beta-tester.
Just FYI, “more”/“plus” button for adding customized tools to toolbar is under review! Hopefully we can implement it in the future!