By Jason Snell

January 10, 2015 1:14 PM PT

Battery life: Apple’s solving for x

Note: This story has not been updated for several years.

Over the years I’ve said numerous times that when it comes to battery life on iOS devices, Apple appears to have a target battery life in mind and builds its hardware—a balance of power-saving software, hardware efficiency, and battery capacity—to hit that number.

It’s an observation born out of reading spec sheet after spec sheet over the years while writing reviews of new iPhones and iPads. Every year, people who are frustrated with their iPhones running out of juice before the end of the day hold out hope that the next iPhone will ameliorate the issue. In general, those people have not been satisfied.

This morning the good Stephen Hackett of the Connected podcast and 512 Pixels sent me a message, asking me if I could point him to a specific story where I had made this observation. I couldn’t oblige him—I’ve made the observation endlessly in stories and on podcasts, but I can’t recall actually writing a story about the trend.

At which point Stephen went away, did the research into Apple’s battery life claims for iPhones and iPads, and came back with numbers which prove my point—to a point.

In fact, when you survey the history of Apple’s battery-life claims—and let’s keep in mind, this isn’t using actual independent test data, but the claims made by Apple based on its own internal testing—you discover that those claims have stayed remarkably consistent over time. It’s only with the iPhone 6 that the base-model iPhone has made a major tick upward in terms of battery life.

But the real gains have been, unsurprisingly, with the iPhone 6 Plus. That’s the device that has truly broken Apple out of its “solve for x” battery-life approach after eight years.

Meanwhile, if you take a look at the quoted battery life for the iPad, you’ll find that Apple’s definitely solving for 10 hours of battery life. That was the quoted number for the very first iPad, and with some slight variation (for a while, for cellular models, it was nine!), it’s been so ever since. Apple keeps making the iPad thinner and lighter, with just enough battery to claim 10 hours of life, no more.

So when you’re anticipating the next model of iPhone or iPad, and wondering if it’ll show markedly improved battery life, keep this in mind: So far Apple has behaved as if the battery life of the iPad and the iPhone are perfectly fine as is, and that it would prefer to create a thinner and lighter model to one that puts the makers of external battery packs out of business.

Except for that iPhone 6 Plus. That thing’s a monster.

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