The waiting is over and two of the most anticipated flagship phones of 2015 have been unveiled and thrust into our very palms. But how do they stack up against one another? We take a look at the latest offerings from HTC and Samsung.
Both HTC and Samsung find themselves in a similar position: needing their new flagship phones to make a big splash in the market.
HTC wants to keep trending upwards after a few years of dismal losses, and Samsung is in danger of sliding the same way if the Galaxy S6 isn't a big success.
Against that background, HTC and Samsung have thrown everything they can at these new phones. They're just about the best smartphone technology these two companies can come up with right now - but do either have what it takes to leave a lasting impression?
There are few surprises from HTC as far as the design of the HTC One M9 goes: it looks a lot like last year's M8, at least from a distance. The full metal uni-body appears again after working so well last time, though overall the handset is a little shorter and fatter than the 2014 edition.
Samsung, in contrast, has shaken things up by fitting the Galaxy S6 with metal sides and a glass back. The appearance is along the lines of the S5, but the materials feel much more premium. There's a thinner bezel than last year's model but no waterproofing and no removable battery.
HTC has chosen a 5-inch 1920 x 1080 pixel screen for the One M9, which puts it some way behind the spec of the display on Samsung's flagship. It doesn't look as far behind as you might imagine though, thanks to some clever use of LCD technology to boost the colours and contrast ratio.
With its Super AMOLED, 5.1-inch 1440 x 2560 pixel QHD screen the Samsung Galaxy S6 has one of the best and brightest displays around - even punching up to 600 nits of brightness when outdoors (which, in non-display speak, is super bright).
The screen on the S5 was excellent in all departments and we're expecting this to be even better. For something a little different, there's the Galaxy S6 Edge of course.
We've been fans of Samsung's Super AMOLED technology for a while now, but it's how the screens look in reality that really matters, rather than how the specifications look on paper - and to our eyes, the S6 just shades it thanks to that jaw-dropping clarity.
The latest and greatest mobile chip - the 64-bit octa-core Snapdragon 810 - sits snugly inside the HTC One M9, so it shouldn't be lacking in the power department, whether you're playing FPS games or playing 4K video. That's combined with 3GB of RAM, making this one of the most powerful phones on the planet.
Over in the Samsung corner, the Galaxy S6 eschews the Snapdragon route for its own 64-bit octa-core Exynos 7420 processor (although that's still to be confirmed from the South Korean brand). Couple that with 3GB of RAM and you've got a handset that, on paper, pretty much outspecs even the impressive M9.
There's good news for fans of a good, streamlined OS, as Samsung's TouchWiz take on Android now comes with fewer apps installed and a much cleaner interface, leaving you to enjoy all the features of Lollipop without distraction.
HTC has opted for Android 5.0 Lollipop too, with its own Sense 7.0 UI on top, which comes with a clever contextual widget to rearrange your apps depending on whether you're at work, home or out and about.
Camera, battery and key features
With the One M8, HTC focused on image quality rather than megapixel count, but this year it's slapped a heavy-duty 20MP snapper around the back of the One M9. Last year's 4MP UltraPixel lens appears around the front.
Samsung doesn't quite match that spec, but our early tests show that the optimised 16MP snapper of the Galaxy S6 is far superior than HTC's Sony-powered effort - although HTC assures us an improvement is coming there.
The inclusion of optical image stabilisation technology should help minimise camera shake, plus the new Pro mode added to the camera software is likely to make for an improvement in quality too.
Not much to separate the two flagships in terms of specs then, but it looks like the Samsung Galaxy S6 has just edged it in practice.
The size of a smartphone's battery isn't the be all and end all as far as battery life goes, but it certainly helps. The HTC One M9 sports a 2,800mAh battery, which is a step up from the 2,600mAh cell inside the One M8. Last year's model did pretty well in our battery benchmarks so we're expecting big things from this year's larger size.
As for Samsung, it's gone for a 2,550mAh battery in the Galaxy S6. That's a smaller battery than the one sported by the Galaxy S5, and even the one in the HTC One M9, but we'll have to wait and see what software and power efficiency tricks Samsung has got up its sleeve before offering a final judgement.
With that QHD screen to power though, things could get dicey for Samsung if the battery isn't perfect.
Aside from the looks and specs of the HTC One M9, its Dolby sound improvements, delivering virtual surround sound both with and without headphones is worth mentioning (despite not really being able to hear much improvement through standard YouTube clips.
The all-metal uni-body (available in gold as well as silver) is perhaps the most distinctive feature, though it's a shame the screen hasn't been upgraded to QHD.
The Samsung Galaxy S6, meanwhile, has a fingerprint scanner that's said to be an improvement on the one on board the Galaxy S5 - it can apparently be activated with a tap, iPhone-style, rather than a swipe. Other than that, the screen is the feature we're most excited about.
Both the HTC One M9 and the Samsung Galaxy S6 have been out in the wild for sometime now and we've managed to have some hefty experience with both.
We really loved the Galaxy S6 giving it four and a half stars in our full review stating it was, "So close to perfect, but a high price and iffy battery really let it down."
As for the HTC One M9 we didn't like it as much as last year's One M8 giving it four out of five stars. Our verdict read, "A great phone if you're upgrading from two years ago, but doesn't deliver enough changes to be worthy of a perfect score."
Both of these handsets are at the top of their game though with only minor differences between the two and a similar price for each.
I'd recommend reading our full reviews for both handsets before you can work out which is the best for you. Check out our full reviews of the HTC One M9 and the Samsung Galaxy S6.