I use Repligo Reader. It's the best program I've used for reading native PDF files hands down. The zoom feature is extremely fast. You can get it half price with a promo code for a limited time.
I'm not sure if it was able to do it before the upgrade to .77 but I'm using that os now and I just pulled up a pdf from my email and it reads it fine. Looks great on the phone too.
Repligo has better zoom. The preinstalled pdf viewer does not zoom as well as Repligo. I also was unable to view PDF files stored on my SDcard with the preinstalled viewer. It seems as though it's used to view Email attachments. Repligo can view PDF files saved from Email attachments to your SDcard, or transfered over via your USB cable. I'm able to read manuals, documents, and all kind of PDF files while on the go. Having them stored on my SDcard allows me to always have access to them.
