I’ve done some serious battery life tests to see how the N95-1 fares, battery life-wise, when playing back music/ video.
The battery was a pretty new one (slightly over a month old), kept on the charger whenever possible to maximize battery life.
The built-in Music Player: 5:00 with WMA + A2DP (~13.5% CPU usage); 5:26 with the same file set and the factory wired earbuds (~7% CPU usage; volume continuusly at moderately loud – 70% - level) with both dis- and enabled equalizer and stereo widening. I’ve run this test twice to really see the effects of the qualizer / widening. Fortunately, unlike with (non-hardware equalizers only effective with wired headphones and nothing else) Windows Mobile, these (with widening, essential) goodies don’t cause any additional battery drain.
MP3 playback (<1% CPU usage) with exactly the same settings (wired headset) flattened the battery in less than 6:20 (dunno exactly when – I’d bet around 6:00? Must be considerably more than 5:26 because of the much less CPU usage but can’t be more than 6:20). This is really bad news.
As far as using the CPU at 100% is concerned, on the other hand, I’ve got much better results than on Windows Mobile. With CorePlayer 1.1.2 beta2, H.264 file playback with maximal backlight level and A2DP (therefore, at ~100% CPU usage): 2:52. This is WAY better than anything on Windows Mobile, assuming maximal backlight and 100% CPU usage.
The test conditions were all the same: disabled 3G (and, with non-A2DP tests, BT too), disabled Wi-Fi scanning, starting with two times fully recharged battery, after a reset, not having anything else in the memory and waiting until the phone shut down. All tests have been made during exactly the same circumstances (same fixed, static position; same external temperature etc). It had very good GSM signal.
All in all,
1. Audio files requiring low CPU time (particularly the MP3 playback test), where I’ve expected MUCH better results, has turned out to be much worse than I’ve expected (and what some people either here or AAS have reported): you can’t expect more than six hours of (continuous) playback of MP3’s, and WMA’s are even worse. Frankly, I don’t know why some people state the phone is able to play back music for more than ten hours. I’m absolutely sure they aren’t right.
2. Video playback (or, in general, running any app requiring (almost) 100% CPU time, with the highest backlight level), on the other hand, fared much better than I’ve thought. The almost three hours I’ve measured is FAR better than with a Windows Mobile device with comparable CPU raw power AND battery. Interestingly, the battery didn’t heat up either (it “only” felt a bit warm) – as opposed to the Windows Mobile case, where 100% CPU usage considerably heats up the battery.