Due to its powerful S1 processor and high quality screen that supports updating at 60fps, Apple has struggled to maximize the battery life of its smartwatch, despite the watch running a stripped-down version of iOS codenamed SkiHill.
Apple initially wanted the Apple Watch battery to provide roughly one full day of usage, mixing a comparatively small amount of active use with a larger amount of passive use. As of 2014, Apple wanted the Watch to provide roughly 2.5 to 4 hours of active application use versus 19 hours of combined active/passive use, 3 days of pure standby time, or 4 days if left in a sleeping mode. Sources, however, say that Apple will only likely achieve approximately 2-3 days in either the standby or low-power modes…
Apple has been testing the battery life of the Apple Watch with pre-bundled and third-party applications. Sources say that Apple is currently targeting 2.5 hours of 'heavy' application use such as gaming or 3.5 hours of standard app use. Notably, when using fitness tracking software, the watch is targeted to have 4 hours of straight exercise tracking on a single charge. When using the device as just a watch, it should be able to display a watch face with animations for three hours straight. While, this seems like a short period of time, in typical daily use the watch face would be off until you wanted to check the time. Apple is shooting for 19 hours of mixed usage each day but it may not reach that for the first version of the device.
Poor battery life has been a concern for Apple and is apparently why the retail launch was pushed back from late 2014 to early 2015. The company has reportedly circulated nearly 3,000 test units of the device to gather data from.
Another issue has been the MagSafe-based inductive charging mechanism which was taking longer than expected to recharge the device. Apple has developed both a plastic and a stainless version of the circular charger. Presumably, the plastic version would ship with the lower end models of the Apple Watch; however, as Apple has only shown the metal variant they may only launch that version of the charger.
It's believed that the Apple Watch is on track to ship by the end of March.Please follow iClarified on Twitter, Facebook, Google+, or RSS for updates.