Some Apps DO bleed battery when on Quick Start dock

[sjinsjca]

The makers of my nav app, CoPilot Live (excellent, btw) advise to kill the app in the quick start doc when you've reached your destination. Of course, it makes sense for a nav app to run in the background. Programmers for other apps that really have no business backgrounding may nevertheless have configured their apps to at least partially remain running. Apple made it easy to do and they may not have considered the drawbacks. This will sort itself out with time. It is also a wise remnder of why unfettered backgrounding is problematic on any portable device. Apple's implementation is a prudent one.

 

[samcraig]

"All things being equal", when it comes to a handheld electronic device with a color screen, speakers, a cellular radio, a gyroscope, a thermometer a magnetometer, ambient light sensors, a microphone, etc., is a difficult state to achieve in any non-lab environment. There's a reason they call it testing in the "wild".

So many little things factor into battery life/drain rate...screen brightness (auto brightness on/off? Was it a cloudy day or sunny?), cellular signal strength (if your local AT$T tower was down one day, the phone could need more juice searching for the next strongest signal). Was it a hot day? Humid? Heat effects battery life. Etc etc.

I've now done the test a total of 8 times (4 on 4 off). Same weather within 5 degrees, same locations. If a tower was out a day, my 8 days of testing would have covered any one day outage.

Of course it's not lab conditions. And I don't expect LAB results. But over the course of the tests so far, there hasn't been a SLIGHT variation. There's been 10-20 percent variation. I'd call that significant.

 

[samcraig]

By the way this is one of the reasons why Apple was so hesitant to do any multi-tasking. Someone above said that they had to close down slacker from the task switcher and it solved his problem. His problem was he was running slacker in the background and it was draining the battery. So everything worked as it was supposed to work. That is the problem with all this stuff, most people don't understand and they think their battery sucks or something is wrong.

Now people can see why Apple was so hesistant to do any multi-tasking and why with what they did they still limited it.

Apple was hesitant for more than one reason (battery life). Apple didn't want to have a task manager. Their belief is that if you have one - then you've failed. Jobs said it at the keynote.

Guess what though? He can talk all he wants - the quick launch bar you double tap IS a task manager. You can dress it up all you want. But if an App is running in the background and you have to physically close it to end it - you're shutting down a task. You are MANAGING a task. The fact that programs that don't multitask just sit in a saved state doesn't make it less of a task bar.

Now maybe this is programming. Maybe developers can put an actual KILL switch in their app (IE - suspend vs quit). But so far it seems that some programs that have started multitasking require user intervention for the ultimate kill switch via the quick switch bar.

So how is that not a "task manager"?

 

[mrblack927]

Words with Friends hasn't been updated for iOS 4, which means it is terminated every time you leave the app. It's not impossible that some combination of WWF and an OS bug is causing excess resource usage, but it's very unlikely.

This is exactly right. It's very strange that a non-iOS4 app would be causing ANY problems at all with power resources that didn't exist in phones running 3.1.x (since it hasn't been updated since then). Has anyone emailed the developer about it?

If we can confirm that the only change is the OS (3.1 -> 4.0) then it's a bug on Apple's side that they need to fix.

 

[Daveoc64]

My quick testing with the "Words with Friends" App (although I used the Lite version) shows that it DOES actually close when you leave the app (with the home button).

I checked using the Activity Monitor (connected to the "Instruments" Application on my MacBook).

That means that it isn't using any CPU - or keeping any RAM even.

 

[admanimal]

If WWF is actually causing excess battery drain after it's quit, it's probably due to an iOS 4 bug that WWF is somehow triggering, which causes the system to continue to do something after the app exits and its resources released. While the bug could somehow be related to the multitasking system, the app itself is in fact terminated when you leave it.