Q: iPhone 4s Battery Life?

Hey Guys,

Try to believe but since I followed this procedure my standby life has increased quite a bit.

A) make a networks settings reset

B) make a soft reset holding power and home till full reboot.

I get to recharge the iPhone every other day.

About the antennas: The link budget in RF (the quality of the RF connection between your device and the cell network or WiFi) is complicated matter and I will not dwell in here. But in general, your device is permitted to have EIRP up to some limit (1-2W today). This is both for being safe for your health and for not intereferring too much with other devices around. The same applies to the base stations, whose limits are much higher, like say 20W. For WiFi in different regions the laws are different, in Europe the EIRP limit is 100mW -- for both your device and the Access Point.

One way to increase EIRP, or keep it the same by lowering the actual electrical power used is to make the antenna more focused. This does work for base stations, that have sector antennas, but cannot work for a handset, because you have no clue in what direction is 'your tower' -- if you had such an antenna, you would have to point the device at the tower for better (or not at all) reception

But here comes MIMO (multiple input, multiple output). It is MIMO, that let's an 802.11n device transmit at up to 150 MBps with one antenna, at up to 300 Mbps with two antennas and up to 450 Mbps with three antennas. Also, because of other reasons I won't dwell in either, having more than one transmit/receive antenna lets your device have longer range, because of better sensitivity and better signal processing. In contrast, the same powered device using one antenna and 802.11g can transmit up to 54 Mbit and at half the distance.

So in summary: by having two antennas instead of one, the iPhone 4S is able to achieve the same wireless performance as the iPhone 4 by using less energy to transmit (less wasted battery) and having more stable wireless connection.

Thanks for the very informative clarification dkalchev.

I guess I was wrong about the dual antenna detail, however the two other specs I mentioned still stand pretty strong.

Hi guys,

I just want to tell you my small story and ask about the issues. I've bought iPhone 4s a week ago and in comparison with my previous iphone and ipad2 the battery life of new toy was terrible. I have found it was losing 1% every 2 minutes of active usage and something about 1% every 10 min in standby mode.

1) At first I read all instructions here and switch off all unnecessary things: push, most of notifications, most of location services, siri, screen brightness and etc. It helped a bit but not to much. I had usage/standby something about 5 hour / 12 hours.

2) Then I made the complete restore, set up iphone like a new device in itunes, created a new Apple ID for it... Tried to prevent uploading of any possible corrupt settings. It didn't help me absolutely.

3) After that I found information about Siri IR sensor, I can't check is it working permanently or not, but I made all described tips to solve the possible issue. And I didn't find any difference in battery life.

4) And the last thing... I found information about noise in iphone speakers when cellular modem works. Well I can hear it in silent room.. the sound like a regular noise from speakers when you have wireless data transfer. I tried to compare it with my ipad2 (3G) and ipad is completely silent. Tried to switch SIM cards between devices and same result: iphone had noise and ipad is silent. The major thing that iphone have noise even in standby mode. Well.. I turned off the Cellular Data on my iphone when I'm not using it and I have new statistics: usage - 9 hours, standby - 32,5 hours. Battery lost only 2% during whole night.

So guys, what do you think about that? What is the issue with my phone? Actually I don't like to switch on/off the cellular data every time, but without this battery is on 4-5 hours. I'm using Apple phones from 2008 and I has already got accustomed to have enabled data transfer permanently. Do you have the same issue? Is it possible to fix it?

omg i have the same exact problem as urs.

i have to turn off cellular data when im not using it,

when i turn on my 3g network/internet, my phone becomes real hot n battery sucking.

but when im on with wifi its battery is definitely not as bad as when im on cellular data/3g.

I'm always with Cellular Data turned off (only connect it when I need to surf the web), and still have phantom usage.

BTW, if your turn cellular data off, you're not turning off 3G.

Do you have WiFi turned off as well?

One possible reason for phantom usage is some application (including Apple's if you are logged in with your account -- like App Store, iTunes Ping etc.) constantly keeps an TCP/IP connection open and (for some reason) does not go to sleep as it should. But this will only happen if you have Internet connectivity on your phone (Cellular Data or WiFi).

If you disable both, and you still have phantom usage, then it is something different.

Still.. on my iPhone 4S I have 3G, WiFi ON all the time, am logged in whatever the phone asked me for at initial setup, + Twitter etc. The phone constantly is connected to Internet and I have verified that it keeps an open TCP/IP connection to push.apple.com, yet at the moment: 73% remaning battery, 1 day 4 hours standby and 2 hours usage. (I know it has higher than typical standby usage, but that's because of the VoIP app I use).

Internet traffic over 3G does definitely draw more power than over WiFi (many reasons, one being that WiFi is way faster and the radio needs to stay ON for shorter periods of time to transfer the same amounts).

These things can be diagnosed, but it gets a bit technical...

really ? cellular data is in setting->general->network right?

if i turn it off, the 3g/edge sign goes off too. and i cant connect to the internet with cellular data off..

or is it just my phone. weird

The Siri sensor should be an issue for additional battery drain while you use your phone, not in standby. The sensor is activated any time your iPone turns it's screen ON. If I ever play wiht Siri, I prefer talking to her without rising the phone to my head so I switch that feature of (Raise to Speak).

Your description of the 'cellular noise in speakers' -- is something new. That is definitely worrysome, because it would mean your phone internal EMI (electromagnetic interference) insulation is very poor.. very strange. This kind of 'noise' is created by induction from the electromagnetic field of your phone into sensitive, long and not well shielded audio signal cables, that then gets amplified by the speaker amplifier and you hear it loudly.

Again, I am very surprised that a mobile device would produce such effect and you should definitely bring it back for diagnostics and eventual replacement.

But there is no way this can have any influence on battery life.

By the way, you don't have to create new Apple ID for 'new settings' -- the Apple ID is not really associated with your phone's settings -- unless of course you use Apple ID to access your backup stored on iCloud.

If you see significant improvement in usage/standby ratio, when you turn Cellular Data then by all means you have some application running in background that uses Internet and does not want to sleep. If you don't have such application, Cellular Data On or OFF would not make any difference, because your 3G radio is on anyway all the time. So you just need to identify which this application is and make it behave.

Yes, only turn it ON when I'm at home or in a place that has Wi-fi.

I already busted my brains out trying to see what's causing the phantom usage, and just can't.

Sometimes my Mail App appears in the Battery Doctor Pro Monitor option (even though I've set Push to OFF and Fecth to Manual or had erased all e-mail accounts from the phone).

Strange thing is: It appears without I turned it ON and it doesn't shows up in the multitask bar...I have to tap the app and THEN tap twice the home button to close it...

BUT, even when it doesn't shows up in Battery Doctor, the Usage time keeps going up...so, that is why I'm not sure it's the Maill App...

I already turned Off the "Raise to speak" too (and rebooted the phone - until you do so, the IR sensor will keep working), with no luck.

Will keep waiting for 5.1...that's how far I'll go.

dervi wrote:

 

really ? cellular data is in setting->general->network right?

if i turn it off, the 3g/edge sign goes off too. and i cant connect to the internet with cellular data off..

or is it just my phone. weird

Yes, the icon goes away, but 3G is still ON. You are just turning off the Data. That is why you can't surf the web. Nothing strange there...

Anyone else noticed mobile mail is still active in the process list, even when push/fetch is off and all set to manual?

EdiMC is correct. With current iOS 5.0.1 on iPhone 4S (only on this iPhone model), if you turn Cellular Data, you switch off the ability of your phone to use the 3G network for data (Internet) connectivity. It does not disable the 3G radio. The iPhone 4S has an 'smart' radio chip, that will select 2G/3G automatically based on some criteria - in general, it will stick to 3G if it sees 3G coverage, even if the 3G network is bad. This is why iOS 5.1 has a switch to disable 3G (and leave you only 2G for voice and EDGE for Cellular Data) -- so that you can have good network coverage in places where your carrier has good 2G, but..  bad 3G network (apparently many network operators have void claims of great 3G networks). The iPhone 4 has a different, 'non automatic' chip and has this option.

The 3G/EDGE/WiFi indicator shows what you use to connect to Internet for data. It will show EDGE if you don't have any 3G coverage.

It seems that Mail runs at all time, but it also seems it is one of the well behaving iPhone apps. You can stop it, if you wish, of course.

Typically, when you shut down your phone by holding the power-off button for few seconds and then power on again, iOS will remember which applications you had open and start some of them again. This is how it 'restarts' an application at power on. To avoid that behavior, you can stop the applications manually before powering down the phone.

sean-g11 wrote:

 

Anyone else noticed mobile mail is still active in the process list, even when push/fetch is off and all set to manual?

Read my post yes, that happens to me too...and it shows up again out of the blue after I turned it off.

sean-g11 wrote:

 

Anyone else noticed mobile mail is still active in the process list, even when push/fetch is off and all set to manual?

Yes! iCloud mail still pushes my messages even when it's set to fetch manually. It seems like it always does this, but I don't get enough message at that account to know for sure whether it's an intermittent problem or a steady bug in the OS.