Can Apple actually test an iPhone battery?

Call them and ask.

It's possible, but I don't think they bother. It's much easier for them to do a swap.

If you want to check, then do the video playback test using the settings listed below.

*Video Playback*

Testing conducted by Apple in May 2010 using preproduction iPhone 4 units and software. Video content consisted of a repeated 2-hour 23-minute movie purchased from the iTunes Store. All settings were default except: Call Forwarding was turned on; Wi-Fi was associated with a network; the Wi-Fi feature Ask to Join Networks and Auto-Brightness were turned off. Battery life depends on the cellular network, location, signal strength, feature configuration, usage, and many other factors. Battery tests are conducted using specific iPhone units; actual results may vary.

From: http://www.apple.com/iphone/battery.html

In addition to those; Do a fresh restore, fully charge your battery, connect Apples headphones(leave the volume half way) and put your phone in a spot with good reception.

+I got 12h 51m doing the video test on my iPhone 4(I made a playlist with the movie Oceans Eleven from the iTunes Store set to repeat over and over).+

Sure they will - they have iPhone diagnostic equipment at the Genius Bar for this which takes seconds.

If the battery has failed, they won't replace just the battery at the store. You will be provided an exchange under warranty.

Allan Sampson wrote:
Sure they will - they have iPhone diagnostic equipment at the Genius Bar for this which takes seconds.

If the battery has failed, they won't replace just the battery at the store. You will be provided an exchange under warranty.

Neat, I didn't know that. But speaking of diagnostic equipment, it would be nice if there was a spot in the Settings.app that listed the battery voltage, mAh and how many charge cycles its been through(like in OSX).

the genius can run diagnostics on your phone, and they do see if your battery is in good condition or not. Just ask the genius to run the diagnostics, they will look at your battery condition. Green = Good, I believe they show yellow and red but not sure, but i'm gonna guess, yellow = okay but may need servicing, Red = bad, need replacement.

@Quad5Ny, I love how Apple has these tech pages on there site. I never seen this one before, the link you provided on battery information. I notice your post says they turn the auto-brightness off. I didn't realize that turning this off is a good way to conserve your battery.

Quad5Ny wrote:

Neat, I didn't know that. But speaking of diagnostic equipment, it would be nice if there was a spot in the Settings.app that listed the battery voltage, mAh and how many charge cycles its been through(like in OSX).

It would be nice, but also leaving a feedback to apple about this would be nice as well.

The Genius bar has software installed in their macs that diagnose apple products...

I took my 3GS back a year ago about battry problems...battery went 100% to 95% on 8hr standby full charge...plugged it in the genius bar and he said " yeah you battery seems weaker than normal...gave me a replacement...

The first time i got the iPhone 4 it was working for about 15 minutes then just died...i thout it was a battery issue so i took it back right away and found out it was a software issue...i asked for a brand new one and not a oem since i literaly just used the phone for 15 minutes