Sync'ing between devices.

[Conrad11]

I've decided to move to an Apple eco system. I have already picked up an iPhone 5 and iPad mini and I am getting an iMac shortly.

Currently I have a Google Apps domain where all my emails/calendar/contacts are stored.

How is best to proceed so I can share everything amongst my devices and still have it accessible from the browser?

I would like to use the reminders and notes apps too.

 

[Conrad11]

Does that sync everything or do I have to sync multiple accounts?

Would it just be easier to use the iCloud and then get my email over exchange or will that drain the battery?