Push or fetch and 3G or Wifi to increase batterylife?

[Reiger]

The batterylife of the iPhone 3G is not so good. Many threads have been posted about this. But I've got a very specific question regarding pushing or fetching MobileMe services and doing this using wifi or 3G. Please hear me out...

I use the iPhone with MobileMe’s push functionality. Where I live (the Netherlands) my 3G reception is excelllent (full bars). However, I do have wifi turned on. Apple states on its site that the phone will last longer using wifi than 3G. However, that’s using Safari to browse the web.

I’m curious about the battery impact of push and pull (or fetch) email. I can find on the web that in general push is more battery efficient, than pulling on a high interval. Only which interval is that? 15 minutes? 30 minutes? I don’t know.

But coming back to the first part. I’m also wondering whether push using 3G is more power efficient than through wifi. It seems to me that it has to connect to wifi every time, while the 3G connection is there permanently. So that’s using power anyway, while wifi is sucking up additional power, especially on very low data-consuming services such as MobileMe’s push functionality.

I’m doing some tests on my own iPhone. However, it’s hard to compare. Because I’m using it as my phone, I cannot create identical conditions, which makes the results more or less worthless. What I've found out so far, is that there seems to be a slight edge to turning wifi off, to increase batterylife when using pushmail. I'm currently testing fetching email every 30 minutes. However, this is only for the purpose of testing, since I'd rather use pushmail (and contact and calendars).

What are your thoughts about this?

 

[Reiger]

It seems that push is the culprit . I've currently set it to 30 minute interval fetch. After 3 hours standby and 30 minutes of use (mosly Safari browsing), the battery still hasn't lost a singe bar.

I am curious how this progresses, but this really sucks as MobileMe is quite worthless if I can't use push

 

[frosse]

Fetch is more battery draining than push since its (often) done using intervals automatically.

So unless you get A LOT of e-mails, push is most efficient.

 

[Reiger]

I don't get a lot of mails, and I really thought pushmail would be more efficient. But in practice it seems that fetching email is much more batteryefficient.

Apperently I'm not alone: http://www.mainstreet.com/new-iphones-battery-falls-down-job & http://discussions.apple.com/thread.jspa?messageID=7567640&tstart=0

 

[steveapp]

Fetch is more battery draining than push since its (often) done using intervals automatically.

So unless you get A LOT of e-mails, push is most efficient.

Sorry but I dont think thats right

Push email means the phone is constantly talking to the server - even when its in your pocket in standby mode, it has to or it wont know there are messages there - there is no way the server can initiate it and send the phone a message in the current setup - thought there is a way to do that I believe.

Fetch is making a quick connection every period (15, 30 or 60 minutes) so making far less use of the network connection. This means the network is used less, the network is a big culprit in battery drain - especially over 3g or Wifi,

Therefore the battery runs out much faster with Push even if your not recieving emails - even with fetch 15 minutes it only takes a few seconds to check ( we will say 15 as a worst case scenario) , hence it is using data for 60 seconds an hour - 1 minute, as opposed to 60 minutes, so in general it is at least 60 times more efficient.

Unless you need your email instantly, 15 minute fetching should be enough for most people - im an email junkie and live by my email connection to exchange and I can manage without push

 

[Reiger]

But that's not the whole story is it? In theory the connection for push services is less intense than really connecting to a server and checking the number of messages (fetch). I don't know which kind of system Apple uses, but f.i. Microsoft Pushmail uses a heartbeat, which should be quite battery efficient.

 

[kis]

Fetch is more battery draining than push since its (often) done using intervals automatically.

So unless you get A LOT of e-mails, push is most efficient.

I agree - fetching uses more power because during each fetch-process the phone goes through the full IMAP authentication process - and IMAP data isn't compressed, either. Pushed e-mails are very small.

Perhaps it would help turning off push for calendar entries and contacts - I can live without that as long as my e-mail works.

 

[kis]

Push email means the phone is constantly talking to the server - even when its in your pocket in standby mode, it has to or it wont know there are messages there - there is no way the server can initiate it and send the phone a message in the current setup - thought there is a way to do that I believe.

Fetch is making a quick connection every period (15, 30 or 60 minutes)

yes, but during that "quick" connection a lot of data is transfered. Handshake, account info (username + password) and the email itself - all uncompressed.
To keep the connection alive on push, only bytes of data are exchanged.

you can make that comparison yourself: go for a month with IMAP fetch enabled and the next with push enabled and compare the amount of data that was transferred. You'll see that IMAP fetch uses up much more data.

The question now is: does it hurt the battery more to have short bursts of several kb of data during fetch operations or does it hurt it more to have a constanst low-level connection with small amounts of data transferred permanently.

 

[steveapp]

yes, but during that "quick" connection a lot of data is transfered. Handshake, account info (username + password) and the email itself - all uncompressed.
To keep the connection alive on push, only bytes of data are exchanged.

you can make that comparison yourself: go for a month with IMAP fetch enabled and the next with push enabled and compare the amount of data that was transferred. You'll see that IMAP fetch uses up much more data.

The question now is: does it hurt the battery more to have short bursts of several kb of data during fetch operations or does it hurt it more to have a constanst low-level connection with small amounts of data transferred permanently.

I understand where your coming from, though I still stand by my argument - I dont think the data amount matters too much except more data takes longer, its the amount of time the radio has to work that makes the difference, though thinking about this I think its more important with 3g and Wifi as the radios for those use far more power.

As Im no longer using 3g all the time as coverage is rubbish where I work, and I dont need the speed really at work so Wifi is off too, I will see how the battery life goes. If my theory is correct, my battery will deplete faster than yesterday.

I connect to exchange 2003, I was told that was less efficient at push than 2007 and sends far more data over all the time, which might make a difference. I dont know if other push - mobile mee or yahoo (was also push wasnt it ?) use a similar technology and are therefore less or more battery efficient.

Time will tell i guess

 

[Reiger]

I'm truly amazed at the difference between turning push on and off. I'm currently testing with fetch (interval of 30 minutes). I've only lost a tiny amount of batterypower (the least the indicator can show). I've got a mixed usage of 1 hour and standby of 5 hours and 30 minutes.

Too bad push is such a battery drain. MobileMe really seems like a waste of money now

 

[kis]

its the amount of time the radio has to work that makes the difference, though thinking about this I think its more important with 3g and Wifi as the radios for those use far more power.

could be - I'm really not sure what depletes the battery quicker. 3G coverage where I work is very good - but it sucks at home for me. As I don't have WiFi at work, I need to keep 3G on during the day.

As for the different methods: I'm not sure but I'd claim that Mobile me uses the same technology as DirectPush (Apple probably licensed it from Microsoft). Yahoo Push was /is IMAP idle if I remember correctly which is definitely the worst of the pack.

Blackberry is far superior in battery conservation. I used to have a Nokia e90 on which I tried both Blackberry Connect and Microsoft DirectPush. While DirectPush would deplete the battery within a day, Blackberry made it last 2-3 days. Blackberry uses an extremely aggressive compression algorithm and reduces the amount of data by about 75% compared to DirectPush.

 

[steveapp]

could be - I'm really not sure what depletes the battery quicker. 3G coverage where I work is very good - but it sucks at home for me. As I don't have WiFi at work, I need to keep 3G on during the day.

As for the different methods: I'm not sure but I'd claim that Mobile me uses the same technology as DirectPush (Apple probably licensed it from Microsoft). Yahoo Push was /is IMAP idle if I remember correctly which is definitely the worst of the pack.

Blackberry is far superior in battery conservation. I used to have a Nokia e90 on which I tried both Blackberry Connect and Microsoft DirectPush. While DirectPush would deplete the battery within a day, Blackberry made it last 2-3 days. Blackberry uses an extremely aggressive compression algorithm and reduces the amount of data by about 75% compared to DirectPush.

After a lot of fiddling I think I have finally come up with a reasonable explination that might even fit all our arguments....

The different network connection methods seem to work in different ways....

If your using GPRS or Edge, the phone is always connected to the network for data. If your using Wifi or 3G (in a 3G area) you only connect when the phone decides it needs a connection - probably because the connection is a big battery drain so its an as needed on system.

This fits with my findings that push makes no difference to battery on edge / gprs but hammers it on 3G and Wifi.

My initial tests were on 3G, not Edge / GPRS hence battery drained.

Interestingly, if you have 3G enabled but are not in a 3G area it runs on EDGE and has all the power savings - which is good for me.

So, you have a choice for reasonable battery life, 3G or Push. Im going to run another day or two on push then switch to 3G and compare.

What I would like to see is 3G access on Safari and other applications, and when theyre not in use fall back to GPRS / EDGE to cope with Push and other stuff when in your pocket. That would give best of both worlds :_)

Stephen

 

[Reiger]

But when using GPRS/EDGE you cannot be called when using a dataconnection (calls are rerouted to the voicemail). Even though I love Visual Voicemail, wouldn't that mean, that using pushmail over a GPRS/EDGE connection means you cannot be called some of the time?

 

[steveapp]

But when using GPRS/EDGE you cannot be called when using a dataconnection (calls are rerouted to the voicemail). Even though I love Visual Voicemail, wouldn't that mean, that using pushmail over a GPRS/EDGE connection means you cannot be called some of the time?

I hadnt thought of that - I know you can be called, and all the phones I've had previously that weren't 3g worked fine, I use data all the time and have never had that problem.

Is it the other way round perhaps, that if you recieve a call it drops the data connection to give you the call ? Nope - your right, just tried having the phone open a huge web page over edge and sure enough, it has not been possible to connect your call!

Eeek thats bad, very bad - time to switch to 3g and Fetch! - and of course its exactly the same because im not in a 3g area! argh

Must enable voice mail now :-(

 

[kis]

So, you have a choice for reasonable battery life, 3G or Push. Im going to run another day or two on push then switch to 3G and compare.

well, I guess I could live with that. Right now I have 3G enabled all the time - but mainly because the phone's new and I'm constantly playing with it, browsing the web, downloading stuff from the app store etc. Once I've gotten used to it, I'll probably just disable 3G and enable it when I need it.

 

[Reiger]

So it is really the combination of 3G and push. I guess I will use fetch then . I'm testing the performance of 3G and push now. But I will probably use fetch in the future...

 

[steveapp]

So it is really the combination of 3G and push. I guess I will use fetch then . I'm testing the performance of 3G and push now. But I will probably use fetch in the future...

I tend to agree, I much prefer push in principal but in practice I dont see much difference between push and 15min fetch.

I must point out though that I push from Exchange 2003, which is far worse than Exchange 2007 aparrently, so milege may vary.

 

[tiggery2k3]

ive been using both a mobile me account and a exchange server both working on push. the only reason i changed to the 3g was because of the fact that no-where near me has an edge signal so this reudced the functionality of the phone significantly (watching youtube at work) but i seem to get better and better battery life everyday. i seem to be getting about 14 hrs at the moment but we shall see what we get when the battery Stabilizes itself. but saying this i do have 3g on constantly and use games other such every now and again. i will run some tests myself and keep them posted. hoping to find some good results

 

[kis]

So it is really the combination of 3G and push. I guess I will use fetch then . I'm testing the performance of 3G and push now. But I will probably use fetch in the future...

The reason why I absolutely need push is that I'm using e-mail to replace SMS. Short messages are insanely expensive here in Switzerland - we pay 25c per message and there are no SMS plans or anything. Since both my wife and I switched to push email instead, we were able to reduce our monthly phone bill by about 20$ each. So I'd really hate to go back to fetch + SMS

At work I don't need push - I'm glad when I don't get my emails instantly there

 

[kis]

I tend to agree, I much prefer push in principal but in practice I dont see much difference between push and 15min fetch.

I must point out though that I push from Exchange 2003, which is far worse than Exchange 2007 aparrently, so milege may vary.

then again, if you read the messages in this thread: https://forums.macrumors.com/threads/523822/ - you'll soon see that most peoples batteries don't last through the day no matter if they use push or fetch.

My latest usage data: charged the phone yesterday at work at about 8 a.m. - it was on all day with push and 3G enabled, WiFi disabled. I was on the phone for about 10 minutes, played some games, downloaded some apps, read news on reader.google.com etc. By the time I went to sleep it still had 30% charge. I turned on Airplane Mode for the night, read an ebook for about an hour while listening to music. The morning it still had 30% charge.

Went to work at 6:30 and the phone lasted until 9:30 until it turned itself off (wanted to know how long it would hast exactly). So with normal (for me) usage (I always turn the Airplane Mode on at night, though) it lasted 24 hours, including 6 hours of usage time - and that's with Push and 3G enabled.

 

[steveapp]

then again, if you read the messages in this thread: https://forums.macrumors.com/threads/523822/ - you'll soon see that most peoples batteries don't last through the day no matter if they use push or fetch.

My latest usage data: charged the phone yesterday at work at about 8 a.m. - it was on all day with push and 3G enabled, WiFi disabled. I was on the phone for about 10 minutes, played some games, downloaded some apps, read news on reader.google.com etc. By the time I went to sleep it still had 30% charge. I turned on Airplane Mode for the night, read an ebook for about an hour while listening to music. The morning it still had 30% charge.

Went to work at 6:30 and the phone lasted until 9:30 until it turned itself off (wanted to know how long it would hast exactly). So with normal (for me) usage (I always turn the Airplane Mode on at night, though) it lasted 24 hours, including 6 hours of usage time - and that's with Push and 3G enabled.

The more I think about it - and use the device, the more confusing this is - I'm now in a pattern of charge overnight, take off charge about 7:30am, use the phone until about 23:00 - maybe midnight, and still have a little charge left - thats with about 5-6 hours use (which i find a lot when I think about it) and if im honest, on an evening i tend to turn wifi on, and during the day I had wifi and 3g and push off - now with push on no real difference, and now i have 3g on too (though no coverage so it defaults back to edge)

What im thinking is the battery conditioning was more important than whas used, though im fairly certain an hour or two navigating with gps would more or less kill the battery outright - will try that sometime I did notice when I had GPS on in the car for an hours drive, with the charger on, it didnt seem to charge the battery so much as just keep the device going

 

[Reiger]

I've interupted the testing of fetching email yesterday, because the differences were extremely large (and I was more curious to the pushmail results).

I've got a mixed usage of 2 hours and 15 minutes, mostly Safari, some calling and some Monkey Ball. Standby time is 21 hours. Then I received the 20% warning... This is with 3G, Wifi, Push (MobileMe) and Location Services enabled.

Currently my iPhone is recharging and this time I'm going to fully complete the testing cycle of fetching email with a 30 minute interval instead of push. I'm very curious

 

[CTK2651]

This may not be scientific, but I've post elsewhere that I'm seeing Push suck the battery dry on my original iPhone w/ v2.0.

I'm in the U.S. and over the last year I'd normally get 2 days on a charge. Since v2.0, I'm getting a day per charge. After lots of trail and error, ie - playing with settings such as Location Service on and off, full discharge and recharge of battery, WiFi on/off, etc. I've come to this conclusion to date. Push is the culprit. Must of my day is spent in the office and commuting w/o WiFi, so I'm living on Edge.

Original iPhone on Edge with Fetch = 2 days / charge
Original iPhone on Edge with Push = 1 day / charge

I admit, I haven't look at the usage stats. Will today (today on Fetch and tomorrow I'll try Push again). Just know what I've been seeing for battery life over the last year, the drop since v2.0 and trying to narrow the cause down.

oh, I have been and con't to use MobileMe. Sync-ing just calendar and e-mail.

 

[Reiger]

Please post an update with your findings .

There are a few other possible causes for short batterylife I read throughout the forums: location services (I doubt it, but some people suspect that the slider has an impact) and maybe the 2.0 software itsself (which I also doubt).

 

[kis]

Another thought - is it possible to set network search to manual on the iPhone?

The HTC TyTN I used to have had very bad battery life with 3G turned on. However, there the culprit was automatic network search - it tended to look for GSM networks whenever the 3G reception got weak (which is probably a good thing by itself but it just kills the battery)