iPhone 2.0 Battery Life and ActiveSync (Bug 29903)

[Jason Hung]

SUMMARY

The iPhone 2.0 software does not put the Zimbra ActiveSync connection into
standby mode, causing the phone battery to be consumed quickly. As tested with an Exchange 2003 installation, the iPhone does go into standby mode with a stock Exchange installation, but not with a Zimbra installation. This bug can render an iPhone unusable in a matter of two hours, since battery life will quickly be drained.

STEPS TO REPRODUCE

1. In iPhone 2.0, add account from the "Mail, Contacts, Calendars" menu in
Settings.

2. Go to "Add Account..." and select "Microsoft Exchange."

3. Enter email address, username, and password. Hit next once. You will be prompted to enter a server address.

4. Enable any service--in particular, the mail service.

5. In the general Settings menu, ensure that the setting for "Fetch New Data" is "Push."

6. In the General menu of Settings, observe the usage time and the standby
time. Record these times on a piece of paper.

7. Ensure that the phone is not plugged to a power source and wait about ten minutes.

8. Observe that the Usage time has increased with the Standby time. Notice that battery life is quickly draining.

EXPECTED RESULTS

1. An iPhone connected to an Exchange 2003 server correctly drops into Standby mode.

2. The same test was applied to an Exchange 2003 hookup. The iPhone Usage and Standby times were recorded. It was observed that the Usage time did not increase when the iPhone was put to sleep--only Standby time increased.

3. The iPhone battery life is close to the expected/rated battery life.

[jjzhuang]

what version of zimbra server do you use?

[Jason Hung]

We're using 5.0.7 Network Edition.

[Dirk]

Our iPhones should be arriving in a day or so and I'm really hoping that this bug does not affect us, but I'll check it out and report back when I know.

[Jason Hung]

It's strange--this bug only affects Calendars and/or Contacts. If I just turn on the Mail service, there usually won't be a problem with battery life. Calendars and Contacts seem to consume a whole battery within 2 hours, while Mail push service seems to be in-line with a 15-minute pull-polling task.

Anyone else using ActiveSync able to post their results here? Our Hong Kong side wants to use the push service when their iPhones come in from Hutchinson/3. We're manually syncing contacts and calendars for now until a better solution exists.

Jason

[jjzhuang]

battery life is not determined by using push or not. it's more about how frequently your mailbox is updated. if you see you consume more battery on calendar sync, maybe there are lots of updates to your calendar. keep in mind a lot of calendar updates are not really visible, like dismissing alarm, but still will trigger a sync with device.

[Jason Hung]

I understand what push and pull is. The problem is it's already downloaded my entire contacts and calendar--there's no reason why it should take 2 hours since I have access to everything right after the account is created. I only have 90 contacts and I only have 5 things on my calendar right now--which is, by the way, test events created to check on the push.

[Jason Hung]

I have a feeling that this may be related to multiple calendars/photo contacts? Anyone else who's using calendar/contact syncing able to chip in? It seems like it's never ending the link to the push server. The device gets very warm.

[jjzhuang]

multiple calendar/addressbook feature was not in 5.0.7.

[Jason Hung]

Yup I know. What I mean is there seems to be some issue with the way iPhone is handling calendars. Is it because there aren't multiple calendars? I'm trying to understand what's causing it to drain the battery in the ActiveSync protocol.