Found and have been using a super simple way to transfer books & pdfs from a Mac -> iPad or iPhone...
It's called CloudUp
After you install it on your Mac it puts an icon in your menubar AND (here's the best part)...
•In the Finder on the Mac, all you do is Right-Click on an ebook file (or pdf) and select "Share On Cloudup" from the pop-up menu.
CloudUp then almost immediately provides a confirmation notification AND auto copies the newly created url link to your clipboard.
•You then simply, paste the link (url) into a note in the Notes app (on the Mac)-be sure you have Notes syncing in iCloud-(or you could email it to yourself etc).
•Go to the iPad, go to Notes app and click the link you put in the note, voila it takes you to the ebook (in Safari) where you can...
a) click download (sometimes have to click "More->Direct URL" if download does not work)
b) then tap "Open in iBooks" (if this disappears after a few seconds, simply tap somewhere in the window in Safari and it will show again)
The ebook will now download and open up in the iBooks app on your iPad.
This is the fastest and most efficient method I have found yet.
***This is also a fantastic, super easy way to share any type of document with someone else - a huge time saver***
https://cloudup.com
-It is a FREE service (you do have to create an account) they are very generous with how much you can share and files size - amazing service!
-Been using it on Mavericks 10.9.5 (works great on OS X 10.10 & 10.11 too)
-I am in no way affiliated with CloudUp, I'm simply sharing a "better mousetrap" solution that I have been using for a couple of years now.
Hope this is helpful.
