comments or to even comment or underline in mobile it becomes very uncomfortable
In reading mode there is no option to view or comment moreover we can not underline highlight in mobiles it becomes so uncomfortable to switch to normal mode to comment and back to reading mode but there also we can't se the added comment
This feature, plus the ability to copy or access other apps in reading mode (e.g. search, dictionaries), are essential to make pdf reading on a phone competitive with Amazon's Kindle's experience....
Having to choose between tiny text (or scrolling) with copying/highlighting on one hand, or readable text without copying/highlighting on the other hand, cancels most of the usability/experience expected for reading in a mobile device