iPhone4s & Zimbra Drain Battery

[epotrzeba]

Ok, have iPhone4s and the battery drains fast. It almost seems that the connection to the server stays open? Have tried on other mobile devices and similar results. Any ideas?

[jonallport]

It almost seems that the connection to the server stays open?

It does! ActiveSync maintains a continuous connection to the server (Zimbra, Exchange, Z-Push, whatever) so that any new mail can be 'pushed' to the phone.

Remember that mobile devices don't have the luxury of assuming there is a constant Internet connection so can't use the 'store and forward' method that's used for server delivery. Instead the handset establishes a 'polling' connection and can therefore handle signal drops, tunnels, network congestion etc. by restoring the connection when connectivity is available again.

If you don't like this behaviour then turn off 'push' and go to polling at set intervals.

I have a 4S and have actually been quite impressed with the battery life (iOS 5.0.1). I can't compete with the Nokia guys' 5-days off the grid, but expect to be able to go from start-of-business Monday to close-of-business Tuesday without recharging, and without skimping on usage.