[milominderbinde]

Read the battery saving tips threads...it was one of the first things that came out that Wifi helps with your battery.

Here are the Extending Battery Life Tips.

WiFi is a big one but so is turning off a number of battery-hog apps instead of minimizing them.

- Craig

[QuarlesLT]

I've been running experiments using Battery Monitor to determine battery life. What I'm discovering is that by far, the single biggest impact on battery life is usage. The more that I use the pre, and data in particular, the less the battery lasts. Using the phone constantly can drain the battery in 3 hours.

Besides usage patterns, here are some things I've observed:

• Strong wifi signal provides significant improvement in battery life
• Poor Sprint signal provides significant reduction in battery life
• GPS off provides minimal to no improvement in battery life
• Bluetooth off provides minimal to no improvement in battery life

Still, nothing consumes battery life more than usage. If I laid the phone on my night stand (where I have good Sprint signal) it would run for about 4 days before draining. If I locked the phone at my desk at work (where I have really bad Sprint signal) it'd run for just under 3 days before draining. But if I use the phone (in the best of conditions - strong wifi, strong sprint, no BT & no GPS) it'll only last 3 hours.

Right now, my results are more qualitative than I'd like. I wish that I had 3-4 pre's available to me so that I could impose identical usage patterns on them at the same time and the same location to determine quantitative differences. But I've just got mine. Anyone willing to lend me theirs for a couple weeks? (Yeah, I know. I crack you up. I get that a lot.)

Alternatively, what I'd really like is the data that Palm is sending to itself. That way I could correlate location and usage across multiple days to get a better sense of usage. Has anyone been able to decipher the data that Palm sends itself?

This is great info! I have definitely determined that usage is the absolute worst drainer, as most days on the stock battery my Pre only lasts about 4 hours, but now with 1.2 and data usage off when I don't need it, I can go over 10 now.

[Impulsebuyer]

Its really not that complicated, I leave wifi on period and have no problems getting emails, txts etc when it goes into sleep mode... Of course more usage drains it faster as does having a poor signal, but my co worker has an iphone and after a year of ownage his battery does not last the day and he must keep wifi off or its worse, so we are lucky in that way, if it wasn't for wifi my phone would prob be dead in a few hours too due to constant roam at work but I force it to sprint only which is another help ...fixing the brightness on the screen and backlits to lowest setting helps too, especially on calls

[mu7efcer]

This made me laugh I would have to concur that using the phone more definitely makes the battery die faster.

Ok. So yeah, that's obvious. But I didn't think that the difference between idle and usage would be so dramatic.

The only exception is the GPS one. If you have GPS on, and providing background info, it will kill your battery. Having GPS on without the background info does not adversly affect the battery as it is not in use.

That's a good distinction. I didn't have background info on. Yet another testing scenario.

[Elysian893]

I'd like to confirm that actually. I've been setting my Pre to Airplane Mode, then separately enabling Wi-fi.

Would EVDO still be on in that scenario?

Yes, because once you turn on WiFi, you're removing airplane mode, so it goes back to normal operations.

[rfceo]

Anyone know which apps are battery hogs? Would be interesting to see which are and look into why they are. Other than the obvious like navigation.

Here are the Extending Battery Life Tips.

WiFi is a big one but so is turning off a number of battery-hog apps instead of minimizing them.

- Craig

[Nextelian]

Crazy question...if you turn off the CDMA radio how do you expect to use the Pre as a phone?

[Elysian893]

Crazy question...if you turn off the CDMA radio how do you expect to use the Pre as a phone?

Different bandwidth in use for voice communications versus data, if I remember correctly.

[Rangt#AC]

I'd like to confirm that actually. I've been setting my Pre to Airplane Mode, then separately enabling Wi-fi.

Would EVDO still be on in that scenario?

No, EVDO is turned off. the only way to use internet in airplane mode is with wifi on in airplane mode.

Yes, because once you turn on WiFi, you're removing airplane mode, so it goes back to normal operations.

Airplane mode + wifi does NOT equal normal operations. EVDO and phone services are off.

And when the phone goes to sleep in this situation, the wifi still shuts off and has to reconnect to router on awake. (airplane mode still on).

so with the 1.2 update, wifi will have to stop this on/off behavior during sleep so that we get emails/chat/tweed while its sleeping with wifi on in airplane mode or evdo switched off.

[phlegm]

I've been setting my Pre to Airplane Mode, then separately enabling Wi-fi. Would EVDO still be on in that scenario?

Yes, because once you turn on WiFi, you're removing airplane mode, so it goes back to normal operations.

Acutally, that's the confusing part. If you turn on airplane mode, then turn on WiFi, the airplane mode icon remains on. (You see only Wifi & Airplane icons.)

So, you're saying that turning on Wi-Fi also turns on EVDO?

So what is left of Airplane Mode - just no phone calls then?

[Elysian893]

Acutally, that's the confusing part. If you turn on airplane mode, then turn on WiFi, the airplane mode icon remains on. (You see only Wifi & Airplane icons.)

So, you're saying that turning on Wi-Fi also turns on EVDO?

So what is left of Airplane Mode - just no phone calls then?

Weird, I did this on my phone on an older version, and the airplane mode icon didn't stay on. It wouldn't make sense for it to, because Airplane mode means no signal, because you're on an airplane! Low and behold though, I just did it on 1.2, and it works this way. Seems a little silly, since you'd miss any calls...

[Rangt#AC]

Acutally, that's the confusing part. If you turn on airplane mode, then turn on WiFi, the airplane mode icon remains on. (You see only Wifi & Airplane icons.)

So, you're saying that turning on Wi-Fi also turns on EVDO?

So what is left of Airplane Mode - just no phone calls then?

look at the post above you

evdo is off in airplane mode, period. it would defeat the purpose of wifi if it turned on evdo.

[Elysian893]

look at the post above you

evdo is off in airplane mode, period. it would defeat the purpose of wifi if it turned on evdo.

It defeats the purpose of Airplane Mode to turn on WiFi

[Rangt#AC]

It defeats the purpose of Airplane Mode to turn on WiFi

i hope that was a joke

Airplane mode is meant so your phone doesn't send signals. wifi can be on in an airplane bc it receives or its just different then cell communication.

interestingly, this was posted on ABCNews today:
Cell Phones on Airplanes - ABC News

But thats neither here, nor there...just on a plane.

[Elysian893]

i hope that was a joke

Airplane mode is meant so your phone doesn't send signals. wifi can be on in an airplane bc it receives or its just different then cell communication.

interestingly, this was posted on ABCNews today:
Cell Phones on Airplanes - ABC News

But thats neither here, nor there...just on a plane.

It was a joke, I think its kind of weird that the phone operates in this manner is all, and didn't even know about it until today. Interesting read about cell phones being allowed, but I wonder if they're "pirocell" thing is compatible with both GSM and CDMA, or could be made to be?

[scrupul0us]

y'know people call me nuts for adding relatives and friends wifi's to my phone (like its all that hard to ask them for the password?) but being on wifi not only helps saves the battery but makes using the phone an overall much more pleasant experience

[Impulsebuyer]

y'know people call me nuts for adding relatives and friends wifi's to my phone (like its all that hard to ask them for the password?) but being on wifi not only helps saves the battery but makes using the phone an overall much more pleasant experience

I agree, its also faster to browse!

[milominderbinde]

Anyone know which apps are battery hogs? Would be interesting to see which are and look into why they are. Other than the obvious like navigation.

You can use the Battery Monitor app to find out about your own apps but basically here is what we have found.

• Apps with ads are constantly online back to the mothership and will destroy battery life.
• Apps that use the GPS continually drain battery life.
• Messaging apps that constantly are reporting that you are available kill you in some cases even when you think you have the app turned off.
• Some apps are just battery pigs constantly updating way more than needed.

- Craig

[gmanvbva]

I'm hoping battery life (among other things) will get better with 1.2.
Although it does not look like it based on others who have loaded 1.2.

If not, I may be looking to get a TP2.

I sit 5 feet from a wifi access point nearly all day at the office and at home.
By 7PM my battery is nearly dead. And that is with minimal/moderate usage...

I have been trying to be patient with the Pre but it is just becoming a serious hassle.

I mean I have about 8 charges, a portable USB charger, 2 spare batteries, etc...
That's just gd ridiculous.

That's not even mentioning some fairly serious annoyances (trying to answer a call???)
I probably have a 50% answer ratio because it is slow to respond on a answer attempt.

And yes, I have wiped it clean twice with webos doctor and still experience the same issues (as does my wife).

[jaroslawk]

I would like to add one correction that should be obvious, but many posters seem to forget about it: turning WiFi on or off has no effect on battery usage if your phone is not using data services (checking e-mails, IM, etc.). If, however, you configured a couple of e-mail accounts like me (especially Exchange and/or huge hotmail mailboxes), updating them via WiFi is consuming significantly less energy than EVDO.
If you go to your e-mail inbox on Pre and notice that synchronization lasts for a couple of minutes ('balls running in circle' icon in the upper right-hand corner is spinning), then you will benefit from WiFi savings. It will be very easy to notice if you set up your e-mail to be checked frequently, let's say every 10 minutes.
After maximizing WiFi usage and reducing frequency of e-mail checks my Pre battery life seems to be almost double when compared to the period a month ago.