Nothing compares to an iPad as a PDF reading device. If you work in fields like electronics engineering, which require quickly going through lots of datasheets

Nothing compares to an iPad as a PDF reading device. If you work in fields like electronics engineering, which require quickly going through lots of datasheets (some hundreds of pages long), it is simply the best device for the job. (BTW, I recommend Readdle Documents for reading PDF because of its unbelievable speed, which matters a lot when your documents are 1200 pages long)