Touch Battery Life tested - Here are the results

[BlackWolf]

hi,
A few days ago I had the idea to actually test the ipods battery life. there are so many "rumors" in this forum on how long the battery actually lasts and how it is drained faster and whatnot, I just decided to do some testing to get some actual numbers.
So, I don't know if this is interesting to you, but I just thought I'd share my results with you.

(btw, my iPod is 8GB, week 47 and SSH was turned off during all tests)

First Test: Music Playback
So first of all I wanted to test the battery life when it comes to music playback. for this test, I created an on-the-go playlist with 10 songs. EQ was set to "Classical", sound check was on and volume bar at ~90-95%. all the files had covers. So I just started the playlist, switched the display off and let it do its job.

Result: 24 Hours

The iPod finally died on me after 24 hours. Since 20 hours is the official number by apple, this is actually quite good. Note that this number may be less in reality, since I had the display on for like 2 minutes or so during that 24 hours which is very likely to be more in reality. But still, you will end up with more than 20 hours.

Second Test: Wi-Fi
So now I wanted to know how long the battery lasts with wifi turned on and in use! For this test I created a webpage that automatically refreshed itself every 10 seconds, put a header in the page to make sure it wasn't loaded from cache and to be absolutly sure every time the page was loaded it showed a randomly created sequenze of 100 characters.

Result: 3 hours

That was quite a bummer. I expected it to be low but THAT low? Well, 3 hours, that's it. For those who are interested: With every page-load there were aproximatly 4 kilobytes of data downloaded. In 3 hours that makes something around 4MB of data downloaded.
Please note that my display brightness was set so around 25% with auto-brightness turned to off. So if you have your display brighter your battery might even last a lot shorter!

Third Test: Display
So after doing the first two test I figured that they were quite uncomparable, since the display was running the whole time during the second test and not at all during the first test. So this third test was basically exactly like the first test, but with the display running all the time. With this test I wanted to know how many power the display needed and how many was actually drained by wifi itself.

Result: 9 hours

Well, somehow what I expected. This means that both Wi-Fi and display are draining the battery almost equally. Wi-Fi a little more than the display but that might change if you touch the display alot or if you have your display set brighter than I had mine.

Result:
The iPod shows quite good results when it comes to music playback, but both Wi-Fi and the display are sucking a LOT of energy (From the 21-hour-difference between music playback only and wifi turned on and in use 9 hours were caused by display and 12 hours by wifi).

I know that there are lots and lots of tests that would be interesting (video playback, wifi on but not using it, SSH, ...) but I didn't have the time to do some more. Maybe I will if I feel like it. I don't know if this is even remotly interesting for you guys but maybe it is, so here you go.

regards
BlackWolf

PS: please no comments on how much free time I have

[jholmes8]

Very interesting. I don't find the results all that surprising and have found battery management rather easy. The reality is, if you use your touch a lot your gonna have to charge it every night (which I don't find a big deal at all). If your on an extended trip that won't allow you to charge often its best to stay away from wifi as much as possible and you'll get good enough battery life on just playing music with the display off to not make it an inconvenience.

[DerekVOF]

Nice job, BlackWolf... I think a lot of people (myself included) will appreciate it...

[dmonk]

Yeah thanks. I don't know why Apple didn't release any stats on battery life in Wifi..maybe because its not good advertisement.

It lasts a lot longer than my Dell Axim 51V...on Wifi, it lasts about an hour and 10 minutes..

[jaimev]

Thanks for the great info. I use my iPod Touch primarily for watching videos.

I did a video test with a single video that was 480x272, H.264 compression, 29.97 fps, with a data rate of 557 kbits/sec, and about 5 hours, 17 min long. (I used Visual Hub to concatenate the 12 episodes (encoded in AVI format) of the Flight of the Conchords, into a single long video clip)

With WiFi turned off, auto-brightness, set to off, brightness set to about the 33% of max, headphones plugged in and volume set to comfortable listening levels, I set the video to run to completion. The video did play all the way through, and I started it up again.

The final results: almost exactly 6 hours until my iPod turned off. About 1 hour more than the Apple spec sheets specified. I have an 16 Gb Touch, week 45.

[paranoidxe]

Cool the battery life for music playback should be well enough for me.

[Lord Entropy]

Nice work man.

Video life would be a good one and I plan on doing that this week when I get mine. Would be good to be able to do a direct comparison with someone else as well.

[dmonk]

Originally Posted by Lord Entropy

Nice work man.

Video life would be a good one and I plan on doing that this week when I get mine. Would be good to be able to do a direct comparison with someone else as well.

Yep I was waiting for that one. I suspect if the encoded video is a higher resolution/ audio bitrate the battery life would be lower?



Also some good news guys!! I did some wi-fi testing under what I consider normal usage, instead of the OP's benchmark of every 10 seconds.

Settings:
auto brightness ON
~20% brightness
working in the evening. (So that means it dims a little under the actual 20% due to detection.)
Disabled EQ settings(this can very slightly effect battery life. I might turn it on later if I like some of them)

1. I was streaming mp3's(about 20-25mb to be more clear)
2. browsing the internet for a period of a little over an hour (on and off. I went to U.S. and foreign websites to read news and forums, test iphone apps)
3. This doesn't include when I was playing music and taking notes down earlier in the day.
Battery life is still far over 90%!



Contrarily, when I had screen brightness at 70%, streaming youtube, I was seeing pretty fast decline in battery. It probably would have died within 3 hours or less. I think the OP made a good point that the brightness and wi fi don't go well together. Of course, the video made a big impact as well.

[RompaRoom]

That wifi 3 hours time freaking sucks, wow!!


Thanks for the info though

[dmonk]

Originally Posted by RompaRoom

That wifi 3 hours time freaking sucks, wow!!


Thanks for the info though

read my results as I did things a little differently and got significantly more battery life.

[BlackWolf]

well, glad you get more. But I have to say I don't get more than 3 hours in daily usage. If I use my wi-fi heavily the 3 hours seem to be very accurate, my ipod dies in no time. of course if I don't use wifi all the time and maybe listen to music in the meantime it will take longer, but at least for me my test seems very accurate. don't think the 10-seconds-reload thing is unrealistic.

but if yours is better good for you

regards

[dlev11]

I know I should know this but, what is SSH?

[BlackWolf]

Originally Posted by dlev11

I know I should know this but, what is SSH?

Secure Shell, a protocol that allows you to access the ipods filesystem and copy/edit files on it after you jailbroke it.

regards

[gonzobman]

Originally Posted by BlackWolf

Secure Shell, a protocol that allows you to access the ipods filesystem and copy/edit files on it after you jailbroke it.

regards

Blackwolf, technically, in this arena, you may be correct, but not so in the bigger world. So I need to correct you a bit. I hate to do that because you're such a great asset to this forum. But...

Being a Unix Admin that uses SSH constantly as part of my job, SSH is a protocol that allows you to make a secure connection between two machines. The "shell" is the command line interface in Unix environment (which is what these little wonders are actually running), much like the "command window" in Windose. Hence the name Secure SHell. Normally this is used to allow secure command line type connections between two machines. In the case of the Touch, it appears (I haven't jailbroken mine... yet) that it will allow you to make a connection to the operating systems kernel, or in other words, lets you open up a "shell" on the machine where you can enter commands. (Correct me if I'm wrong in the case of the Touch. Like I said, I haven't used it yet on a Touch.)

I'd be very interested from those of you that use it, does it allow you to connect to another machine via wifi and what version of SSH does it use (V1 or V2) if it does?

-G

[DerekVOF]

Actually, on the iPod Touch, the SSH does allow you to send commands via the shell to the kernal, but it also allows for SFTP connections as well for the transfer of files...