In this comparison we’re looking primariy at the specifications. For more in-depth information on each phone you should also see our full Samsung Galaxy S6 review and LG G4 review, and check out our S5 vs S6 and G3 vs G4 comparisons.

LG G4 vs Samsung Galaxy S6: Price and UK availability 

The LG G4 was announced at the end of April and will go on sale in the UK on 28 May. It’s priced from £499 SIM-free for the entry-level 32GB ceramic version (add £25 for leather), which makes it exactly £100 cheaper than the comparable and already on sale Samsung Galaxy S6. The S6 was announced earlier this year at MWC and went on sale on 10 April. If you’re buying either phone on a contract, you can expect the monthly tariff to be a little cheaper for the LG G4. Also see: Where to buy the LG G4 and best Samsung Galaxy S6 deals. 

LG G4 vs Samsung Galaxy S6: Design and build 

We’re not convinced by the leather-clad LG G4, and our personal preference would be the cheaper ‘ceramic’ (that would be 5 percent ceramic, 95 percent plastic) version. The leather is genuine and its colour will apparently fade over time, but we prefer our phones made from metal or glass to cow hides. (What phone material floats your boat? Vote now in our poll.)  And that’s exactly the route Samsung has taken with its new Galaxy S6. Finally answering to the cries of cheap, plastic build quality, the S6 now features a metal chassis and tough Gorilla Glass 4 front and back. The Galaxy at last looks and feels like the premium smartphone it is, but you’ll want to try it in store before you buy – the Blue Topaz model has a nasty mirror shine, and all that glass has a tendency to pick up fingerprints, which are more visible on the coloured versions (blue or gold) than White Pearl or Sapphire Black. You don’t get this problem with leather, although we’ll have to wait and see how that handles wear over time. The LG G4 is available in six colours. Also see: Best smartphones 2015.   However nice it looks, though, Samsung has angered many fans by ditching the removable rear cover. No longer can you swap out the battery for a spare, nor add in a microSD card for storage expansion. If either of these things are important to you, the LG G4 has a 3000mAh removable battery and supports microSD up to 128GB, while Samsung has gone down the Apple route asking you to pay up front for extra storage.  It’s not the only difference between these two phones either. While the LG G4 has a nicely curved, diamond textured rear that fits comfortably in the hand, plus the useful Rear key seen in the LG G3, Samsung has squeezed the S6’s hardware into a 7.1mm (thicker than the 6.8mm quoted by Samsung when measured in our lab) case, which leaves the rear camera protruding by an extra 1.6mm. We’re not too keen on this, although with the S6 fitted into a protective case you won’t notice the difference. Also see: Best Samsung Galaxy S6 cases. 

Both these phones are fitted with Quad HD displays, the LG’s at 5.5in and Samsung’s at 5.1in, making for a sharper 577ppi display on the S6 against the 538ppi G4. The display technology is different, though, and while Samsung favours the saturated colours and deep contrast of Super AMOLED, LG has gone for an IPS Quantum Display. It says this has 20 percent greater colour reproduction, 25 percent improvement in brightness and 50 percent greater contrast than standard IPS, which traditionally has much more realistic colours than Super AMOLED. Advanced In-Cell Touch tech combines the LCD and touch layer in a single sheet, making for improved sensitivity and colour reproduction. Which screen you prefer will be a personal choice – both are superb, and among the best on the market right now.  Given the difference in screen size there is also a difference in size and weight between these flagship Android phones. While the chunky 155g LG G4 measures in at 76×9.8×149.9mm, the Samsung Galaxy S6 is a svelte 138g and 70.5×7.1×143.4mm (as measured in our lab). Also see: Best Android phones 2015.   Two things Samsung offers that LG can’t match are the heart-rate sensor, which can now also be used as a dedicated capture button for the selfie camera, and fingerprint scanner. The latter is vastly improved over that on the Galaxy S5, and now works with Apple-style touch- rather than swipe input, and that means it actually works. It’ll become more useful still when Samsung’s own Pay mobile payments service comes to the UK later this year. Also see: Samsung Pay UK release date. 

LG G4 vs Samsung Galaxy S6: Hardware and performance 

Samsung’s Galaxy S6 is one of the fastest phones we’ve ever tested, built around a 64-bit octa-core Exynos 7420 processor (with four 1.5GHz A-53 cores for efficiency and four 2.1GHz A-57 cores for performance), 3GB of LPDDR4 RAM and Mali-T760 graphics. Also see: What’s the fastest smartphone 2015.  We’ve not yet tested the performance of the LG G4, but doubt very much that its six-core (2x A-57, 4x A-53) Qualcomm Snapdragon 808 chip will be in the same league as the Exynos chip inside the Samsung Galaxy S6. The reduced power of the processor is said to improve battery life over the LG G3 by 20 percent, however, and performance will still be fast – only those who demand ultimate power will be disappointed. The LG G4 also has 3GB of RAM, and it uses an Adreno 418 GPU, which supports 3D gaming on 4K displays.  The Samsung Galaxy has a smaller 2550mAh battery which, as we mentioned earlier, is no longer removable. Both phone batteries support wireless charging (but the G4 no longer does so as standard – only when fitted with the Quick Circle case), and the S6 also features quick-charging technology that Samsung says will give you enough power for four hours use in 10 minutes.  While the LG G4 comes with 32GB of built-in storage and support for up to 128GB via microSD, plus 100GB of additional Google Drive cloud space free for two years, the Samsung Galaxy S6 matches the 100GB of cloud storage with its preinstalled OneDrive app, but lacks the microSD support. If you want more storage you’ll have to pay for it: add £60 for the 64GB model; the price of a forthcoming 128GB model is yet to be confirmed. Also see: How to back up Android. 

LG G4 vs Samsung Galaxy S6: Connectivity 

As flagship phones both LG G4 and Samsung Galaxy S6 support all the connectivity options you could dream of, with dual-band 802.11ac Wi-Fi, Bluetooth 4.1, NFC, GPS, GLONASS, USB OTG and an IR blaster.   Both are sold as single-SIM phones in the UK, with support for 4G. The LG G4 supports LTE-Advanced for download speeds up to a theoretical 450Mb/s, while the S6’s Download Booster can pair Cat 6 LTE and Wi-Fi for faster downloads over 30MB.  Only the Samsung Galaxy S6 features wireless charging as standard (the LG requires a Quick Circle case), a fingerprint scanner and a heart-rate sensor. 

LG G4 vs Samsung Galaxy S6: Cameras 

Samsung and LG both fit their flagships with 16Mp rear cameras. The G4’s has an f/1.8 aperture, optical image stabilisation 2.0, laser auto focus, a new z-axis and a Colour Spectrum Sensor that allegedly works better than an IR sensor to understand and adapt to ambient light. The S6 has an f/1.9 aperture, optical image stabilisation, automatic real-time HDR and IR Detect White Balance. The camera is always running in the background, and launches in a fraction of a second with a double-tap of the home button. Both can record 4K video.  At the front Samsung specifies a 5Mp selfie camera, and you can use the rear-mounted heart-rate sensor as a capture button. LG bests this with an 8Mp selfie camera on the G4. 

LG G4 vs Samsung Galaxy S6: Software 

Both Android Lollipop phones, the LG G4 and Samsung Galaxy S6 are running the latest flavour of Android and both will be upgraded to Android M when it becomes available.  However, software is a key talking point for these phones given that the S6 runs the infamous TouchWiz UI, which has previously put off potential customers from purchasing a Samsung phone. Happily, we can report that TouchWiz has been overhauled for the new Galaxy: it’s less laggy, and there’s less bloatware preinstalled (there’s still rather a lot, but you can at least hide much of it from view and even uninstall some apps). There was a lot of talk of Samsung preinstalling Microsoft Office, but actually you just get OneNote, OneDrive and Skype.  Meanwhile, the LG G4 comes with the UX 4.0 UI, which adds new features such as Quick Shot, Event Pocket and improvements to the likes of Smart Notice and the Gallery app. As with the S6, there is a little less bloatware preinstalled.  We’ll cover the software running on each phone in greater detail in our standalone Samsung Galaxy S6 review and LG G4 review. 

LG G4 vs Samsung Galaxy S6: Verdict 

It’s impossible to give a definitive verdict until we’ve run the LG G4 through our benchmarks, but based on the specifications alone we can judge that the Samsung Galaxy S6 is the higher-specified phone with what we expect will be much faster performance, as well as more bells and whistles including wireless- and quick charging as standard, a heart-rate sensor and a fingerprint scanner, while the £100 cheaper LG G4 offers better value and the added benefits of a microSD card slot and removable battery.  Read next: Best new phones coming in 2015.  Follow Marie Brewis on Twitter. Marie is Editor in Chief of Tech Advisor and Macworld. A Journalism graduate from the London College of Printing, she’s worked in tech media for more than 17 years, managing our English language, French and Spanish consumer editorial teams and leading on content strategy through Foundry’s transition from print, to digital, to online - and beyond.

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