Power out: Have smartphone batteries reached their peak?

The Great Smartphone Conundrum. The time has come – we're going to have to choose between performance and battery life. Smartphones keep getting faster. If you buy a new high-end phone this year, you'll find it's noticeably more powerful than last year's best gadgets. It will let you run much more demanding apps, it will load up web pages more quickly, and it will deliver sharper, more advanced videos and games.

This might not sound like a big deal – aren't new gadgets always faster than old gadgets? Yes, that's true. But what's striking about phones is how quickly they're getting quicker. This year's top-of-the-line phones are likely to be twice as fast as those released last year. And last year's phones weren't slouches – they were twice as powerful as the ones that came out in 2011.

This pace is remarkable. If you study the speed increases of smartphones over time, you notice a thrilling trend: phones are getting faster really, really fast – much faster, in fact, than the increase in speed in the rest of our computers. If you scrutinise this quickening pace, though, you're bound to get disillusioned.

One of the reasons phones have been getting faster is that they're also getting bigger. A bigger phone allows for a bigger battery, which allows for a faster processor. But now we've hit a wall in phone size: Today's biggest and fastest phones carry screens of around 5in, and they're not going to get any bigger than that. (If they did, they wouldn't fit in your hand.)

So if the size of our phones – and, thus, the size of their batteries – is now fixed, phone makers (and phone buyers) must make a sharp trade-off. Over the next few years, at least until someone develops better battery technology, we're going to have to choose between smartphone performance and battery life. Don't worry – phones will keep getting faster. Chip designers will still manage to increase the speed of their chips while conserving a device's power.

The annual doubling in phone performance we've seen recently isn't sustainable, though. Our phones are either going to drain their batteries at ever-increasing rates while continuing to get faster – or they're going to maintain their current, not-great-but-acceptable battery life while sacrificing huge increases in speed. It won't be possible to do both.

To understand how fast phones have been getting, let's look at some numbers. There are lots of ways to measure the power of computers. One of the most popular is a program called Geekbench, which tests the processor and memory of a machine and spits out an overall performance score. Such "benchmark" scores don't necessarily correspond to how a specific machine will perform in all situations – if you run a buggy app on a fast phone it will be slow – but they're helpful in painting a picture of a device's potential.

Primate Labs, the company that makes Geekbench, has posted a handy database of scores on its site – a way to see how various phones, tablets and desktop and laptop PCs stack up. According to the site, the first and second iPhones, which Apple released in 2007 and 2008, earned Geekbench scores of 136 and 137, respectively. Compared with PCs, these scores were terrible – the first couple iPhones were slower than any Mac that Apple put out in the 2000s. (One of the early clamshell iBooks, which Apple released in 2000, scored 176 on Geekbench.)

But then, in 2009, the iPhone began to take off. The iPhone 3GS got a Geekbench score of 276, twice as fast as its predecessor. The iPhone 4 was about 33 per cent faster than that, and the iPhone 4S, released in 2011, was nearly twice as fast as that. Then, late last year, Apple released the iPhone 5, whose 1,599 Geekbench score more than doubled the 4S's mark, and edged out every other phone on the market, too. Compare that with the original iPhone's 136, and the progress is remarkable: in the five years between the first iPhone and the iPhone 5, Apple increased the speed of the device by a factor of 12.

It's not just Apple's phones that are seeing incredible speed increases. The six-month-old iPhone 5 is now looking creaky beside the Android smartphones being released this year. The new HTC One earned a Geekbench score of 2,535 – 60 per cent more than Apple's top-of-the-line phone. And Samsung's upcoming Galaxy S4 posted a stunning 3,163, twice as fast as the iPhone 5.

In fact, the S4's score is high enough that just a few years ago, it would have ranked as a pretty respectable full-fledged PC. Apple's 2009-era MacBook Pro, for instance, scored around 3,200 on Geekbench. In other words, today's fastest phones are comparable to four-year-old high-end laptops. If next year's phones can again double their performance – scoring around 6,300 on Geekbench – they'd be comparable to MacBook Pros released in 2012. That would put the fastest phone at just two years behind high-end laptops.

Then, if smartphones can again double their speed to hit 12,600 on Geekbench, they'd be just as fast as today's best MacBook, the 15in high-resolution "Retina" model. But I doubt that will happen. As thrilling as it is to consider a limitless horizon for smartphone performance, we're already starting to see phones struggle to keep up with their current super-fast chips. The HTC One, for instance, has got raves for its performance, but early reviews suggest its battery has trouble going all day with anything more than light usage.

Battery tests on the Samsung Galaxy S4 show that it can last a full day for heavy users, which is pretty good – but that's primarily due to the fact that Samsung squished a bigger battery into the phone compared with last year's S3. Samsung isn't going to have much room left in the Galaxy to do that next year. It will face a choice: will it try to double the phone's performance or maintain a day's battery life?

Different phone makers will make different choices. Some companies will go for raw speed to attract geeks who care about specs. Others will market their devices according to what they can do rather than how fast they can do it. Apple, in particular, has long taken pains to maintain its devices' battery life from year to year, so it might focus on usability rather than trying to set the smartphone land-speed record.

But be warned: You, as a phone buyer, will have to make a choice. The most powerful phones are going to be much more pleasant to use than everything else on the market – until about lunchtime, when you'll need to recharge them. The phones with the longest battery life, on the other hand, might stutter as you put them through their paces and won't let you play the latest games or other demanding apps – but at least they'll be around when you need them at midnight. Which is better, a fast phone or a long-lived one? I really don't know. I want both. But the days when you can have the best of both worlds in one package will soon be gone.

This article originally appeared on slate.com