For OED, there is no app or ebook, so your best bet is subscribing to the OED web site: http://www.oed.com/subscribe/
For a Periodic Table, check out http://www.freewarelovers.com/androi...able_1.3.1.apk
Couple of things you didn't mention are enhanced note tracking (BI Notes
- nice for accumulating typed notes against a given starting topic) and mind mapping (Thinking Space
- useful for sketching out essay structure), both available from the enTourage App Store (you'll need to access these from your eDGe to be able to download and install them.