The LG G5 stands out from this year's batch of smartphone upgrades in giving us something genuinely new to talk about. Its modular approach, letting you clip in spare batteries and camera packs and speakers, brings a touch of innovation to a market that seems to be leveling out (at least in terms of new ideas, if not actual specs).

If you've missed our earlier coverage, the bottom section of the LG G5 slips out, together with the battery. That means you can pop in a spare battery or use one of the "Friends" accessories: right now they are the LG Cam Plus (camera grip and physical controls, along with some extra battery power) or the LG Hi-Fi Plus with B&O Play (Hi-Fi audio with DAC and the Bang & Olufsen seal of approval).

There are other Friends accessories that don't slot into the phone itself: the LG 360 VR (LG's take on the mobile VR craze), the LG 360 Cam (for all your 360-degree video recording needs), the LG Rolling Bot (like BB-8 with a camera), a Bluetooth headset, high-end B&O headphones and even a drone controller.

Others may follow, and from other companies besides LG, but that's what's been announced so far. More than anyone else this year, LG has focused on the accessories to its flagship smartphone to try and reach the front of a crowded line-up.

First, though, the phone – where LG has abandoned last year's experimentation with leather and plastic to craft an all-metal aluminum unibody for the G5. It looks respectable and premium without ever coming across quite as gorgeously crafted as something like the Galaxy S7, HTC 10 or iPhone 6s, and that's the running theme here.

It's the same story with the display: a high level of quality that's just a shade less impressive than what LG's rivals are putting together. Around the back the fingerprint sensor doubles as a power/lock button, which is a little annoying when your phone's flat on a desk.

Meanwhile the always-on display that other manufacturers have played around with is a very welcome upgrade that LG says only drains 0.8 percent of the battery an hour. Why hasn't this become standard much sooner? Samsung has its own variation in the Galaxy S7 and S7 Edge models.

On their own, the LG G5's style, design and performance aren't enough to beat the Samsung and HTC flagships for this year, so it's down to this intriguing modular design to help it woo buyers.

A small switch lower down on the left-hand side lets you eject the current module and slot in a new one. You don't have to turn the phone off first, though obviously it loses power the instant the battery comes out (there's no reserve, unfortunately).

It's not the smoothest and most straightforward of operations and to begin with you'll think you're going to snap the battery in two. It does get easier over time, but it doesn't feel fluid or natural enough to be something you're going to be wanted to do all that regularly – and remember you need to reboot each time too.

For this review we tested out both the LG Cam Plus and a spare battery pack with the phone. The former adds a satisfyingly chunky grip to the G5 and brings another 1,200 mAh of power as well, and while you can still charge the phone with the camera module added, you can't charge it and use the extra buttons it brings at the same time.

Those buttons let you zoom (digitally ... which is essentially real-time cropping), power the unit on and off, and take photos and videos. There's also a little switch to fire up the camera app at any time. Does all of this make the phone easier to use as a camera? Well, yes, a little. Are you going to ever take the time to swap in the Cam Plus before taking pictures? Probably not. After all, it doesn't actually improve the quality of the pictures themselves. That extra battery juice is useful, but it's easy to just bring a spare and use the standard camera controls.

Keeping the LG Cam Plus loaded all the time could be an option, but it adds too much bulk to the phone to be a viable choice.

There are two lenses around the back of the LG G5, giving you a choice of 78-degree or wide-angle 135-degree shots. As you would expect from LG, picture quality is among the very best, with colors crisp and accurate in almost all settings, as well as a low level of noise. Low-light performance was really good too, though I only had two older phones (the 2015 Nexus 6P and 2014 iPhone 6) to compare it with directly.

The LG G5 achieved better colors than the iPhone, though didn't record as much detail. However, it beat the Nexus 6P in both counts. These photos were taken in very dim conditions, with very little visible to the naked eye, so the G5 can certainly hold its own in low light, even if it's not right up there with the best (images have been resized and cropped but not otherwise modified):

It's the 135-degree wide-angle lens we really like, letting you get in much more of that beach, landscape, group shot or building. And it's here where the Cam Plus shows its worth too, letting you zoom seamlessly from a wide-angle to a standard view without any real sign that you've switched from one lens to the other.

The spare battery is perhaps more useful as an accessory, even if it's less exciting, giving you another 2,800 mAh worth of power when you're out and about and far from a power socket. It comes with both a charging dock and a slim carrying case so you can pop it in your pocket after charging. If you want a modern flagship phone with a removable battery, the LG G5 is pretty much the only option out there right now.

What's more, LG seems to have excelled in getting great battery life on this handset. Before we started reviewing the G5 in earnest it sat around on standby (switched on but locked) for 3-4 days without running out of power. That's obviously not the way a smartphone is typically used but it's a good sign. It doesn't drop much at all overnight, for example.

In our official battery test, where we run a streaming video app for an hour at a preset level of luminance, the charge in the LG G5 dropped 8 percent. That's the best score we've seen, compared to 9 percent for the Samsung Galaxy S7 and 11 percent for the HTC 10. Both of the latest iPhones, meanwhile, fell by 13 percent.

That's impressive and might well be one of the main reasons to pick up the LG G5.

LG's UI skin doesn't add anything significant and is discreet enough not to spoil the Android experience, going for a simple black and white aesthetic in most places. One useful feature is the ability to add extra software keys between the back, home and overview buttons at the foot of the interface.

One of these buttons can be used to quickly show or hide the notification panel, which is handy when your thumb is down near the bottom of the phone.

It's also worth noting that the G5's 32 GB of on-board storage can be upped by a further 2 TB with the addition of a microSD card. However, Android's adoptable storage feature isn't supported, so internal and external memory can't be blended together to appear as one.

There have been some great flagships released this year and no doubt Apple, Samsung, Motorola and Google have more to come before the end of 2016. In that context, the LG G5 doesn't quite hit the same heights in all of the key areas, though camera quality and battery life are certainly right up there with the best.

We like the idea of smartphone modules but in practice the G5's don't feel particularly useful or compelling, especially when you weigh up the extra cost (US$70 for the LG Cam Plus and an expected retail price of $150 for the LG Hi-Fi Plus with B&O Play, for example). They're something else to buy and carry around with you ... which would be fine if they were must-haves. But they're not.

The best Friend here is the phone accessory we've had for years, the spare battery, and if you're one of those people who still values that then you're going to be much more interested in the LG G5 than everyone else.

The LG G5 is by no means a bad flagship. It excels in its camera and battery life, and the modular approach is refreshing to see. We'd love to see more modules and better modules added further down the line, which would make the design sacrifices that have been made to accommodate them worth it. Ultimately though, unless you're taken by the Friends ecosystem of products, there are better top-end handsets out there.

The LG G5 is available now at an average price of around $630 full retail in the US. That's cheaper than the offerings from HTC and Samsung so far this year, but, if you're going down that road, see if you can grab some deals on a Friend or two as well to make it better value for money. Otherwise you'll likely be paying more than better rivals to get the complete package.

Product page: LG

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