Best app for reading/annotating PDFs

After going through iAnnotatePDF, PDF Expert. I have to say, this is the best app by far in annotating and reading PDF files. The files are very easy to organize and you are able to make folders. The tools are intuitive, and the flipping animation gives it a ibooks feel reading quality. The app also saves your files on iCloud, which makes switching from iPhone to iPad a seemless experience. I highly recommend this app.

5ingularity about PDF Box, v1.1.3