What does a waterproof IP rating mean?

IP stands for 'Ingress Protection' and is used to define the sealing effectiveness of electrical enclosures against intrusion from foreign bodies and moisture.

The first number refers to how the device sealed against solid particles like dust; the highest you can get is '6' meaning total protection. The second digit is for water protection and the best you'll see on most is '8', going by the original IEC standard 60529 (6K and 9K are not part of this).

It's worth noting that ratings water ingress are not cumulative beyond 6, so a device with a rating of 7 doesn't have to compliant with the water jet element of 5 and 6.

If an IP rating has an X in it, don't misinterpret this as the device having no protection. It's likely to have good protection for particles if it's IPX6, but the rating has not been formally allocated.

1. Samsung Galaxy S8

Samsung has taken the best phone around and made it even better with an impressive Infinity screen and premium design. It ticks a shedload of boxes - as you'd expect from a flagship. It's the best phone of 2017 so far, but it is expensive and the biometrics are a let down. The OnePlus 5 is already a strong competitor, and we're keen to see what Apple can offer in way of a challenge with its iPhone 8.

2. LG G6

The LG G6 is no doubt a striking smartphone. Metal and glass shimmer while the huge 18:9 screen is impressively brought to life with the improved software and its rounded corner design. It is a more refined smartphone than both the G4 and G5, and should appeal to a broader audience – even if its features aren’t the same globally.

There’s a lot to cover with the G6, and it’s a complicated phone to assess. The differences in hardware and the tweaks in software mean that is a phone that reveals itself to you slowly than the immediacy of, say, a Samsung Galaxy S. The design looks uniform at first until you realise how well it all comes together.

LG has quietly managed to build a mature phone with next to no bezels and some genuinely unique tweaks to software, leaving it feeling fresher and more creative than any Android phone we’ve seen for a while.

3. Sony Xperia XZ Premium

The Sony Xperia XZ Premium is a stunning smartphone, both in terms of design and performance. The mirror-like look isn’t for everyone due to the appearance of smudges, but it helps provide an elegant, high-end look.

The 4K HDR display is one-of-a-kind, bright and vibrant, and shows off snaps taken by the impressive Motion Eye camera perfectly. The camera itself can handle almost anything you can throw at it, although performance does slip in low-lit conditions and the super slow-mo video mode takes some practice.

If you’re looking for a gorgeous high-end smartphone with a huge focus on display and cameras with above average battery life, the Sony Xperia XZ Premium is a solid option.

4. Samsung Galaxy S8 Plus

As with the regular Galaxy S8, we're really impressed by the Galaxy S8 Plus. Samsung has done a great job of making last year's phones even better. However, with both offering the infinity edge screen and the unwieldy size of the S8 Plus, there's little reason to spend the extra.

5. Apple iPhone 7 Plus

The iPhone 7 Plus is an excellent phone. It’s Apple’s best yet, but it is also Apple’s most expensive yet, with a huge starting price. In some respects, the upgrades seem to justify this, but at the same time some features are arguably only catching up with what the competition has been offering for a while now – water-resistance for one.

Taken as a whole, the performance, battery life, camera quality and stereo speakers are all compelling reasons to upgrade. But our advice remains much the same as for the iPhone 7: if you already own the previous generation, there’s not enough here to justify ditching a 6S Plus, especially if you’re halfway through a two-year contract. Those just coming out of contract on the iPhone 6 or 6 Plus would do well to grab a 7 Plus. 

6. HTC U11

There's a lot to like about the HTC U11 and while it certainly has flagship level specs, it's hard to differentiate in the market against the likes of Samsung and LG. The glossy and colourful design is fresh but won't be for everyone, even though we're glad it's finally waterproof. The key is wether you want the squeezable Edge Sense feature which is useful at times but not something we're blown away by.

7. Apple iPhone 7

The iPhone 7 is an evolution of the 6S, so if you were expecting a revolution you’ll probably be slightly disappointed. However, aside from the underwhelming battery life, it is an excellent phone. It’s waterproof, has fantastic cameras and performance, and the new stereo speakers sound great. There’s now 32GB of storage as a minimum, which helps to mitigate the higher prices.

8. Samsung Galaxy S7

The Samsung Galaxy S6 was the best phone of 2015 and, although it’s still early days, the Galaxy S7 is a serious contender for best phone of 2016. Samsung has taken into account what its fans want, addressing the three main areas of concern: removable storage, waterproofing and battery life. It’s also upgraded the core hardware and photography gear, added an always-on display and some useful software. Right now the Galaxy S7 is simply unbeatable.

9. Nomu S30

The Nomu S30 passed our durability tests with only superficial damage to the rubber case, standing up to both dunking in water and a launch across our patio. It has a large, bright screen, and decent performance for most users, but falls down on its camera quality, size and weight.

10. Ulefone Armor

A capable rugged phone at a very good price, the Ulefone might not be the fastest handset out there or have the best screen but for many people it prove ideal.

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