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Asus Zenfone 6 Review - Battery Life and Verdict Review


One of the Asus Zenfone 6’s key features is its gigantic battery. It has a 3300mAh unit.

It’s even bigger than the Xperia Z2’s battery, and let’s not forget that this phone has a 720p screen – and of course the Xperia Z2 is a top battery performer. In our usual video test, which involves playing a 720p MP4 video until the battery dies, the Zenfone 6 lasted for just under 11 hours.

Given this phone has a 6-inch screen, that’s a good result. Sony’s phone still betters it, but the Zenfone 6 trounces the other phones in the Zenfone range. The Zenfone 4 didn’t even make it to five hours. Asus Zenfone 6

It’s in normal use we saw the best results. With moderate use, you can get more than two days out of a charge. Three at a push, if you’re careful.

To provide some anecdotal evidence, on one day we started with only 67 per cent battery charge. However, with just that we made is through the day and up ’til lunchtime in the next. This is the sort of phone you really can be quite blasé about charging.

Like the Zenfone 5, though, you can’t remove the battery, meaning there’s no way to carry around a spare if you’re going to be away from a plug for a long time.

Asus has also tried fairly hard with some other secondary elements of the phone too (it’s sad to think of battery life as secondary, but in phone marketing terms it is). The call speaker is unusually loud to cut through noisy environments.

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Having extra volume on tap is handy, but in pushing the presumably tiny driver as hard as the Zenfone 6 does the mid-range gets rather harsh at top volume. And, if you’re like us, your natural inclination is to max out the call volume as standard.

The internal speaker is a little less remarkable. It uses a single driver on the back, so there are no stereo shenanigans going on here. Sound quality is nothing remarkable, but passable.

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The question of whether you should buy the Asus Zenfone 6 needs to be countered with another: are you sure you really need or want the Zenfone 6? We’re not trying to dissuade you from upgrading your phone, but are you sure you want a 6-inch one?

Even the leap from a 5.5-inch phone is significant. And while we got used to the Zenfone 6’s size, we found the phone often ending up in a bag rather than a pocket because of its sheer size.

The Zenfone 6 does nothing in particular to help its cause either. It offers no software optimisation for the screen, and its resolution is no greater than the 4.5-inch Moto G. Of course, for things like gaming, video-watching and even browsing, a bigger screen is generally better.

Among 6-inch phones this is a top contender. Most of last year’s models have now been discontinued, there are few actual 6-inch alternatives, and it sells for a good deal less than phones like Sony Xperia T2 Ultra and HTC One Max were originally on sale for.

However, we can’t help but feels its efforts to be ‘more premium’ than the Zenfone 5 have backfired a tiny bit. At £250 the Zenfone 6 is a decent deal. But cut down the camera and CPU to the 5-inch version’s level, and get that price below £200 and you’d have a rather more remarkable phone. Still, Asus has done pretty well here.

Like any 6-inch phone the Asus Zenfone 6 is not for everyone, and its huge display could be sharper. But we quite like all its other aspects, particularly its very impressive battery life. Combined with a competitive price this makes for a decent phone-tablet hybrid.

Next, check out our list of the best mobile phones

Trusted Score

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Score in detail

  • Performance 8
  • Camera 8
  • Design 8
  • Battery Life 9
  • Value 7
  • Software 8
  • Calls & Sound 8
  • Screen Quality 7

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