The Apple website now contains a subsection on the use and maintenance of iPhone batteries. The company claims that in general, the iPhone's lithium-ion supply should power up to eight hours of talk, seven hours of video, six hours of Internet use and as much as one full day of audio playback; standby time is 250 hours (10.4 days). Apple says, however, that by the time an iPhone has been fully charged and discharged 400 times, the battery's capacity will drop to 80 percent or lower. At this stage, users can either accept the reduced usage or pay for a replacement.

Some tips are suggested on forestalling the need to recharge. The most basic is to always lock the phone when it's not in use, but Apple also recommends specific settings. When they are not in use, for instance, both Bluetooth and Wi-Fi should be disabled, as they continue to drain power while waiting for a connection. Turning on Auto-Brightness will only keep the screen as bright as it has to be, and disabling the iPod Equalizer will reduce strain on the CPU. Crucially though, users must ensure that any EQ settings for iTunes are set to Flat, because these are carried over when an iPhone is synched.

Lastly, Apple notes that maximum capacity is only achieved in temperatures of 32° to 95°F in use or -4° to 113°F in storage. Some cases may generate excess heat, so it is recommended that in these circusmtances, users take their iPhones out before charging them.