I use an app I wrote myself. It allows me to download and view the En Route Supplement Australia via 3G, Wifi or manually via a PC. Its currently on the Apple App Store (iERSA).
I've just added some new features so that I can upload word and PDF documents (ie. checklists) and view them.
I can also download and view a pre-flight briefing (Area forcecast, TAFs, and NOTAMS, ATIS, RAIM)
Screenshots attached. I'm going to publish the update on the App Store if its useful to others. If you have a US iTunes account I'll be giving away 20 free download keys when the update is released in a week or two. Send me a private message and I'll put you down for a key.
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