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spiff72 · Dec 15, 2007, 05:25 PM

I did a comparison with my iPhone and my wifes this week, charging both overnight (Monday night). They were both unplugged around 7am on Tuesday with full charges.

Neither of them of them got much use over the week. I checked them today (Saturday) at about noon. Mine was still showing half-full according to the icon on the top of the screen, and about 4 days and 4 hours of standy (with 1-1/2 hours of usage).

When I checked hers, the battery was completely empty, showing the "plug me in" icons.

I am trying to figure out whether my battery life is really good, or is hers really poor?

Any thoughts?

imitchellg5 · Dec 15, 2007, 05:28 PM

Yours seems pretty good, although you don't use it much. Did she use hers more than you used yours? 4-5 days is pretty normal for most phones.

spiff72 · Dec 15, 2007, 05:58 PM

I think they were used about equally (mine might have gotten a bit more usage) during this time.

Perhaps mine is just unusually good?

imitchellg5 · Dec 15, 2007, 06:57 PM

Yeah, it would seem like yours is pretty good. That happens sometimes. My iPod shuffle will play for almost 22 hours straight, and it's rated at 12. My mom's will make it only about 16 hours.

gradient · Dec 15, 2007, 07:03 PM

What I've noticed with mine is that I get significantly better battery life if I drain the battery completely (or as close as is practical) before recharging back to 100%. If I do that I get a 2 days of life out of it with regular use. If I don't I'll get 1 day with similar useage. I always use it regularily for browsing and media, keep main checking every 15 mins and like to keep the screen brightness all the way up, mind you - pretty much everything you're not supposed to do if you want to get max battery life out of it. But hey, I bought it to USE it!

Macfreak7 · Dec 18, 2007, 12:19 PM

To the OP, maybe your brightness setting or some other setting was different which caused that?

AppleJockey · Dec 18, 2007, 12:21 PM

Wait did you say SATURDAY
asin 5 days later?

I do the same charge over night thing (wi fi & blue tooth off)off)talk surf and ipod for less than a full hour combined
and by 11pm im getting ther 20% left message

Originally Posted by spiff72

I did a comparison with my iPhone and my wifes ...............

Any thoughts?

spiff72 · Dec 18, 2007, 07:30 PM

I hate to brag, but yes, it was Saturday when I checked again.

I finally checked it again at the end at the end of my workday on Monday, and it gave me the low-battery (under 10%) warning. I am amazed by the battery life on this iphone (6-1/2 days) - I had bluetooth on (it is paired with my car and connects automatically), and wi-fi was off.

I have the brightness set to automatic on my phone, I will have to check my wife's later.

analogue SPRINKLES · Dec 19, 2007, 01:29 AM

Couple days of heavy usage. More than reasonable for its size and features.

jjj888 · Dec 20, 2007, 10:49 PM

My Ipod touch seems to last about a week, slight less. Not on constantly but I use it for a couple hours a day doing various tasks.

Cadaver · Dec 25, 2007, 10:57 PM

Originally Posted by AppleJockey

Wait did you say SATURDAY
asin 5 days later?

I do the same charge over night thing (wi fi & blue tooth off)off)talk surf and ipod for less than a full hour combined
and by 11pm im getting ther 20% left message

Both my iPhone and my wife's seem to be sensitive to the AT&T signal strength - if the signal strength is good, the phone will last for days on standby no problem. If signal strength is poor, it'll be 50% down or more within a day.

I get almost no cell signal in the building when I'm at work, so, to prevent me from ending up with a dead battery by the end of the day, I turn on Airplane mode when I'm in the building. This way, even with frequent use, my iPhone goes many days without needing a charge.

andrewbw · Dec 26, 2007, 11:05 PM

Cadaver (and all) --

This is pretty common knowledge, but it bears repeating in this thread: Don't forget that cell phones, every so often, transmit a ping to the closest cell tower saying, in essence, "I'm here! Here's who I am!" This is how the cellular system finds your phone in order to deliver an incoming phone call, among other things.

The power with which a cell phone transmits this ping, along with its transmissions when you use data services, or make phone calls, varies with how close you are to the cell tower. If it has to broadcast more powerfully in order to maintain its link to the cell tower, it will drain your battery faster. As you move around throughout your day, you may experience periods of strong signal (5 bars) or weak signal (1 or 2 bars). The ratio of these extremes has a cumulative effect on battery life. One would expect people who own iPhones in dense urban areas where cell coverage tends to be "blanketing" (no or few weak signal zones) would have better overall battery life than those people who live in suburban or rural areas where cell coverage is more variable, or even non-existent. Nothing will drain a cell phone faster than a no-service area, since the phone repeatedly attempts to engage a tower at as high a signal level as it can, and only backs down once it can lock contact. Hence your experience in your workplace.

Keep this in mind when attempting to compare iPhone battery life -- even if the phones were bought at the same time and used in roughly the same locations, it's not possible to compare their charge life without removing or mitigating this variable.

Cold Warrior · Dec 26, 2007, 11:08 PM

Yes. This is often measured as RSSI by the tower, and the tower (i.e., the network) can command your phone to user a higher power output when communicating with it, if it reads your phone's RSSI as too low or inconsistent.

Krusty · Dec 27, 2007, 01:28 AM

I get about a day and half on a full charge (one full business day and then until 6 or 7 in the evening of the second day). So, effectively I get 2 business days of use out of it. I use the phone portion irregularly but I do push a lot of data through it ... numerous emails in (and a few out), text messaging, google maps/weather/stocks etc on a fairly regular basis. I'm in my office about 50% of the day (and up and about the other half). I barely get a signal in my office but it increases to 4 or 5 bars as soon as I step out.... so I don't doubt that uses a lot of juice to stay tower-connected when I'm in the office.

Overall, pretty good but nothing like the 4 or 5 days that some people get.

AppleJockey · Dec 27, 2007, 02:09 PM

Originally Posted by andrewbw

Nothing will drain a cell phone faster than a no-service area.

well maybe wifi

Originally Posted by Cadaver

Both my iPhone and my wife's seem to be sensitive to the AT&T signal strength - if the signal strength is good, the phone will last for days on standby no problem. If signal strength is poor, it'll be 50% down or more within a day.

I get almost no cell signal in the building when I'm at work, so, to prevent me from ending up with a dead battery by the end of the day, I turn on Airplane mode when I'm in the building. This way, even with frequent use, my iPhone goes many days without needing a charge.

got ya makes sense