Educate me on usage

heycal

macrumors 6502a
Original poster
Jul 25, 2013
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I'm currently using an iphone 4, and before that an android. With both devices I've always fretted about battery life. I've been with iphone 4 for a few months now, and only now realized I could see my usage amounts.

It seems I'm getting about 5 hours of usage/16 hours of standby. I'm at around 30% brightness, 1 hour of podcasts a day, 50-100 text mesages a day, and minimal web browsing or other use. Early on I read an article on battery saving tips and implemented most of them. Normally I'm at home, and when I go out, it's generally within a couple of miles of my house.

So, what does this all mean, and how might things change when, say, I travel tomorrow on a train from New York to Boston, and spend the weekend up there? What kind of things affect usage and in what ways? And how is usage even measured -- the amount of time the screen is on or something?

Enlighten me, please, folks.
 
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scaredpoet

macrumors 604
Apr 6, 2007
6,627
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So, what does this all mean, and how might things change when, say, I travel tomorrow on a train from New York to Boston, and spend the weekend up there?
First and foremost, bring your charger. :)

Second: Does the train you're going to be on have Wifi? If so, I would suggest using it. Having your phone on Wifi will use a bit less energy than going on 4G or LTE.

If you DON'T intend to use WiFi, then turn WiFi off completely. If WiFi is turned on but not connected, your phone will expend energy attempting to search for a familiar network to connect to.

One drawback to WiFi being off: When you use anything with location services, the phone will nag you that turning Wifi on will increase accuracy. Annoying, but don't give in.

What kind of things affect usage and in what ways?
I would suggest reading this guide from a former Apple Store staff member, that details his observations about what causes battery drain. As it turns out, some of the things we do that we think might help conserve battery (like quitting apps) may actually be consuming more power.

And how is usage even measured -- the amount of time the screen is on or something?
Screen-on time is one component. Another is if background activity is occurring that requires a draw on the CPU and other resources. So, playing music or streaming audio counts as usage, even if the screen is turned off. So is fetching e-mail.
 

heycal

macrumors 6502a
Original poster
Jul 25, 2013
719
15
First and foremost, bring your charger. :)

Second: Does the train you're going to be on have Wifi? If so, I would suggest using it. Having your phone on Wifi will use a bit less energy than going on 4G or LTE.

If you DON'T intend to use WiFi, then turn WiFi off completely. If WiFi is turned on but not connected, your phone will expend energy attempting to search for a familiar network to connect to.

One drawback to WiFi being off: When you use anything with location services, the phone will nag you that turning Wifi on will increase accuracy. Annoying, but don't give in.



I would suggest reading this guide from a former Apple Store staff member, that details his observations about what causes battery drain. As it turns out, some of the things we do that we think might help conserve battery (like quitting apps) may actually be consuming more power.



Screen-on time is one component. Another is if background activity is occurring that requires a draw on the CPU and other resources. So, playing music or streaming audio counts as usage, even if the screen is turned off. So is fetching e-mail.
Good article, and good information from you, thanks.

So use wi-fi when available, like it is on Amtrak's trains? But if I'm only texting or phoning on the train, turn it off?

Let's say I'm traveling by car, bus, commuter train, or just on a long walk by foot through a village or city. Is the phone constantly searching for a signal? If so, is that killing the battery?

I went to a football game in a different state and 45 miles from my house last week. Later that evening, my phone was out of juice much earlier than usual. What exactly is the reason for that, the searching for wi-fi?

Also, I'm guessing many things you can access with wi-fi OR cellular, like maps and weather apps and so on and so forth. If so, should one be in the habit of turning off their wi-fi whenever they leave the house to go out and about since there's no upside to having it on? Seems a pain on short hops though.
 

scaredpoet

macrumors 604
Apr 6, 2007
6,627
342
So use wi-fi when available, like it is on Amtrak's trains? But if I'm only texting or phoning on the train, turn it off?
If that's all you're doing, and don't plan on using any data at all, sure. But if you do plan on using data, even a little bit, just leave it on. Power cycling the Wi-Fi multiple times will only waste battery, more than it saves.

It's almost like stopping and starting the engine on an older car. There's a certain amount of fuel wasted in the startup process... so turning the engine off for very short periods and then starting up again can actually waste fuel. That's why non-hybrid gas cars aren't normally shut down at stop lights. (Hybrid cars can get going again on electric power, so the shutdown is offset by the savings through electrical usage.)

Let's say I'm traveling by car, bus, commuter train, or just on a long walk by foot through a village or city. Is the phone constantly searching for a signal? If so, is that killing the battery?
Any time you have a wireless radio on and it's not actively connected to a network, it's searching for a network to connect to. That uses energy.

I went to a football game in a different state and 45 miles from my house last week. Later that evening, my phone was out of juice much earlier than usual. What exactly is the reason for that, the searching for wi-fi?
Could be lots of reasons. Searching for WiFi could be one factor.

Was it an NFL game? If it's a venue with a huge crowd (multiple thousands), another real issue there is cell network capacity... lots of phones overloading the local cell sites and competing for access on the network. A phone connects to a cell network by locking on to a pilot channel, broadcasting its ID and waiting for acknowledgement. An overloaded cell network won't necessarily "hear" a lot of the phones "shouting" at it, or will take too long to respond back, and that means the phones will keep trying. That too, uses a lot of energy.

Also, I'm guessing many things you can access with wi-fi OR cellular, like maps and weather apps and so on and so forth. If so, should one be in the habit of turning off their wi-fi whenever they leave the house to go out and about since there's no upside to having it on? Seems a pain on short hops though.
Ultimately, you have to consider the costs and benefits of all this. You can definitely overthink what you're doing, and all that effort might take more time than it's worth to save the small amount of battery power it saves. Then there are things that actually use up power, like quitting apps and too-frequently turning radios on and off.

I don't know if you're seeing really short battery life and maybe that's why you're worrying about all of this. You mentioned having an iPhone 4, and I'm wondering if maybe that battery on your phone is just worn out. If you plan on keeping that phone for much longer (like a year or more), maybe investing $79 in a new battery might help things out quite a bit.
 

ROLLTIDE1

macrumors 68000
Sep 12, 2012
1,791
549
If that's all you're doing, and don't plan on using any data at all, sure. But if you do plan on using data, even a little bit, just leave it on. Power cycling the Wi-Fi multiple times will only waste battery, more than it saves.

It's almost like stopping and starting the engine on an older car. There's a certain amount of fuel wasted in the startup process... so turning the engine off for very short periods and then starting up again can actually waste fuel. That's why non-hybrid gas cars aren't normally shut down at stop lights. (Hybrid cars can get going again on electric power, so the shutdown is offset by the savings through electrical usage.)



Any time you have a wireless radio on and it's not actively connected to a network, it's searching for a network to connect to. That uses energy.



Could be lots of reasons. Searching for WiFi could be one factor.

Was it an NFL game? If it's a venue with a huge crowd (multiple thousands), another real issue there is cell network capacity... lots of phones overloading the local cell sites and competing for access on the network. A phone connects to a cell network by locking on to a pilot channel, broadcasting its ID and waiting for acknowledgement. An overloaded cell network won't necessarily "hear" a lot of the phones "shouting" at it, or will take too long to respond back, and that means the phones will keep trying. That too, uses a lot of energy.



Ultimately, you have to consider the costs and benefits of all this. You can definitely overthink what you're doing, and all that effort might take more time than it's worth to save the small amount of battery power it saves. Then there are things that actually use up power, like quitting apps and too-frequently turning radios on and off.

I don't know if you're seeing really short battery life and maybe that's why you're worrying about all of this. You mentioned having an iPhone 4, and I'm wondering if maybe that battery on your phone is just worn out. If you plan on keeping that phone for much longer (like a year or more), maybe investing $79 in a new battery might help things out quite a bit.
Why would it have to be an NFL game ? more people go to college football games than NFL games:D
 

scaredpoet

macrumors 604
Apr 6, 2007
6,627
342
Why would it have to be an NFL game ? more people go to college football games than NFL games:D
You're right actually. I work on and near college campuses a lot and I remember my phone would be pretty much useless, because a game was on. Don't know why i missed that. :)
 

deeddawg

macrumors G3
Jun 14, 2010
8,981
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US
Why would it have to be an NFL game ? more people go to college football games than NFL games:D
*Some* college football games. Bryant Denny isn't the norm for all college football... :cool:


One factor I didn't see mentioned -- signal strength. The cellular radio transmitters in phones are variable power. The phone will boost transmitter power to the level it needs to "be heard" by the cell towers (up to the maximum). So if you have a poor signal or tons of competition for hitting the tower, the phone boosts transmitter power and subsequently chews up the battery. Similar concept to talking with a friend sitting next to you in a quiet room vs shouting at them from a distance in a noisy environment; you can do the first all day long yet the latter tires you out quickly.
 

heycal

macrumors 6502a
Original poster
Jul 25, 2013
719
15
For the record, it was an NFL game, Broncos at Jets to be precise.

So, would it fair to say that 1) When I go to Boston this weekend, I should leave wi-fi off for the entire weekend since I don't think I'll be in one place for very long or spending a lot of time on the internet this weekend? I guess there could be the occasional map look-up or googling of restaurants and movie theater and such, but that could take place on random street corners, etc -- and should I make this a general practice when traveling? B) When entering a place like a football stadium where a couple of hours, beware of battery drain?

Here's another example of a typical situation for me: I'll take a commuter train into Manhattan to see a friend for dinner and a night out. This often entails long random walks around the city. There is little use for the phone during this time beyond the occasional text, google lookup, or such. Is leaving the wi-fi on for 6 hours under this scenario a serious drain on the battery and a reason to turn it off, or is pretty insignificant?

To the person who asked: my iphone 4 seems to get about 5 hours of usage on a normal day. I think that's decent for an iphone 4, if I read right.
 
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heycal

macrumors 6502a
Original poster
Jul 25, 2013
719
15
So if you have a poor signal or tons of competition for hitting the tower, the phone boosts transmitter power and subsequently chews up the battery. Similar concept to talking with a friend sitting next to you in a quiet room vs shouting at them from a distance in a noisy environment; you can do the first all day long yet the latter tires you out quickly.
Nice. I like me a good analogy::)
 

heycal

macrumors 6502a
Original poster
Jul 25, 2013
719
15
I realize I almost never use my phone for much internetin'. Maybe 30 minutes tops a day, spread out over many one or two minute spurts of retreiving email and glancing at it, taking a peek at Facebook, checking the temperature a couple of times, etc.

That being so, should I leave wi-fi on all day long as I generally do now? Would it be better to leave wifi off as a rule? If I did, would it save much juice?
 

scaredpoet

macrumors 604
Apr 6, 2007
6,627
342
That being so, should I leave wi-fi on all day long as I generally do now? Would it be better to leave wifi off as a rule? If I did, would it save much juice?

Depends on two things: Is your phone set up for push notifications/e-mail fetching, and are you normally near a WiFi hotspot that you connect to?

If yes to both, then just leave WiFi on. When connected to Wifi, the phone uses slightly less energy during data usage. So any random e-mails and notifications that come through will tax your battery less if you're connected to a stable WiFi hotspot.

Though if you rarely connect to any WiFi throughout the day, then just turn WiFi off.
 

heycal

macrumors 6502a
Original poster
Jul 25, 2013
719
15
Depends on two things: Is your phone set up for push notifications/e-mail fetching, and are you normally near a WiFi hotspot that you connect to?

If yes to both, then just leave WiFi on. When connected to Wifi, the phone uses slightly less energy during data usage. So any random e-mails and notifications that come through will tax your battery less if you're connected to a stable WiFi hotspot.

Though if you rarely connect to any WiFi throughout the day, then just turn WiFi off.
My email is set to manually retrieve email, not push. Yes, I spend most waking hours near my home's wifi. HOWEVER, I'm using my laptop for internet use during that time, and only using my phone for texting during that time.

Away from the house and out and about, I'll use my phone for texting of course, but also to check email, the weather, facebook, occasional restaurant or map lookups, etc. But that's all very brief and limited. A minute here, two minutes there. No sustained or heavy internet usage at all.

So, that being so, is there any reason for me to turn on wifi every day? And if I didn't, what kind of power savings might I see?
 

scaredpoet

macrumors 604
Apr 6, 2007
6,627
342
You could try it to see, but I'm skeptical that you would see a significant power savings. Even if you're not actively using data on your phone, there is still some residual data usage here and there. I'm thinking it would be best to just have it connected and leave it there.

Again, this goes a lot towards overthinking it, and whether the savings is worth the effort. Most people (myself included) really don't think so actively about whether our phones are using too much energy or not, and for the most part it works out okay anyway.
 

heycal

macrumors 6502a
Original poster
Jul 25, 2013
719
15
Again, this goes a lot towards overthinking it, and whether the savings is worth the effort. Most people (myself included) really don't think so actively about whether our phones are using too much energy or not, and for the most part it works out okay anyway.
Well, sure, you can overthink these things, but it seems to me that figuring out whether the default wifi mode for me should be "on" or "off" would be worth figuring out. Just figure out which is smarter, leave it on that setting, and I'm done thinking about it.
 

heycal

macrumors 6502a
Original poster
Jul 25, 2013
719
15
Screen-on time is one component. Another is if background activity is occurring that requires a draw on the CPU and other resources. So, playing music or streaming audio counts as usage, even if the screen is turned off. So is fetching e-mail.
I'm trying out an LG G2 at the moment. In their version of the usage section is something called screen "time on". I can get 5 hours or 5 hours of screen 'time on' it seems. Is that not comparable to iphone's 'usage' because iphone usage includes other things, and thus if one gets 5 hours of "usage" it's not the same, or as good as, 5 hours of screen 'time on' on G2?
 

scaredpoet

macrumors 604
Apr 6, 2007
6,627
342
I'm trying out an LG G2 at the moment. In their version of the usage section is something called screen "time on". I can get 5 hours or 5 hours of screen 'time on' it seems. Is that not comparable to iphone's 'usage' because iphone usage includes other things, and thus if one gets 5 hours of "usage" it's not the same, or as good as, 5 hours of screen 'time on' on G2?
There's been a lot of debate about this. My take on it is that "screen on" doesn't tell the whole story. There are lots of times where the phone is active, but the screen is off. IN those cases, the one will still use more battery than when the phone is truly at rest.

Others argue that the screen on time is important in itself. It would be nice if both platforms had both options... a "usage" and a "screen on" stat.
 

heycal

macrumors 6502a
Original poster
Jul 25, 2013
719
15
There's been a lot of debate about this. My take on it is that "screen on" doesn't tell the whole story. There are lots of times where the phone is active, but the screen is off. IN those cases, the one will still use more battery than when the phone is truly at rest.

Others argue that the screen on time is important in itself. It would be nice if both platforms had both options... a "usage" and a "screen on" stat.
So hard to compare battery performance given the different methods in keeping track of use?
 
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