Im not wild about this app. I dont hate it either, but I use it for marking up a musical score (I sing in a chorus). It is kind of cumbersome to use in mark up since each little circle you make around a note or rest require 2 taps to get to the markup tool. Sometimes complex markups like scratching out a lyric and typing in another causes the app to crash.
I have used it for signing contracts that came as PDFs and for that type of use it seems good.
Studiovoltaire about PerfectReader Pro - PDF & Document Reader for Adobe Acrobat & Microsoft Office