Compare Epocrates to PDR

Timeliness
Epocrates strives to provide the most up-to-date drug information, incorporating new drugs as soon as possible as well as incorporating updates to prescribing information.
Evidence-based medicine
Epocrates goes beyond the package insert / prescribing info / research / review information from sources including the FDA, clinical practice guidelines and primary literature to provide the most accurate, current and clinically relevant drug information. Additionally, Epocrates includes evidence-based off-label dosing information when deemed appropriate (PDR only provides prescribing information, thus providing no deviation from what is available in the prescribing information and no off-label dosing info.)
Inclusion of generic products
Epocrates has monographs for both brand and generic products, whereas PDR only provides information for brand products.  Beneficial for formularies and generic drug availability.
Drug Look Up
Epocrates Rx allows you to look up a drug either by its brand or generic name, but PDR only allows you to search by brand name.
Pricing
Epocrates provides approximate retail price, whereas no pricing information is available by PDR.
Pill pictures and pill identifier
Epocrates provides pill pictures and a pill identifier free online, whereas PDR does not appear to have this content or functionality.
Formulary
Epocrates formulary is user friendly.
MobilePDR
reproduction of PI information and no deviation from PI; limited information and includes drugs only if they are in PDR; no pricing information; DDIs include multiple statements as well as distraction of insignificant interactions.