If there’s one constant we’re seeing from smartphone reviews this year, it’s that you should only expect one day of battery life. Why is this, and what can you do about it?

Why you should only expect one day of battery life

Every year, we see new phones.

There are hundreds of them, and they bring new features to an already packed house, offering better cameras, faster processors, brighter screens with more pixels, faster mobile internet speeds, updated WiFi, stronger Bluetooth, louder speakers, infrared ports, the ability to track your footsteps and heart-rate and so much more, you begin to wonder just if you can still call these gadgets a “phone” (and the answer is yes, because they still make phone calls).

Bringing all of these features to handset is one thing, but keeping the size down is another, and so the battery tends to suffer, because we all want something truly capable, but we want it in a form that is thin and light.

This means the battery has to be kept on a diet, because the bigger the battery, the heavier the handset, but there’s a catch: all of these features have to be optimised for the battery, and if they’re not, they may end up shooting your battery’s life in the foot.

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Take the screen, for instance, which is the biggest killer of a smartphone today.

You switch it on and lots of little pixels light up, relying on the battery to fire up over two million pixels if you have a Full HD display, and over 3.5 million pixels if you’re on a more pixel-packed 2560×1440 display, the sort used on the Samsung Galaxy S6 and LG G3/G4 handsets.

That’s a lot of pixels to deliver power to, and it is one of the biggest reasons why smartphone screens can stop smartphone batteries dead in their tracks, diminishing the life of a smartphone quite severely.

As such, phones with less pixels to power generally handle battery life better, and so if you look at a phone with a 5 inch 720p HD screen and another with a 5 inch 1080p Full HD display, there’s a good chance that the one with the lower screen resolution — the first one out of those two — will perform better, especially if the specs are otherwise identical.

In fact, if you rely less on a smartphone screen, you’ll find your battery life will improve, but it’s not the only thing to make a dent.

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Processing power and the graphical prowess can also make a dent, as do these extra features, such as a more capable camera, because it likely relies on some camera guts that use the battery, while GPS tends to draw more power than most expect and loud speakers require a fair amount of power themselves.

All of these things, all of these little bits that go into a smartphone, help to make a phone’s battery last a day, which is the new norm.

Essentially, if you buy a flagship phone every year, you should generally expect only a day of life, with a nightly charge.