Samsung and HTC both know what it’s like to be the top Android device maker. Samsung currently occupies that position, but HTC is struggling to climb back from a tough couple of years. Samsung has stumbled in the past year, but the newly announced Galaxy S6 is its chance to turn around slumping sales. At the same time, HTC is looking to keep its recent momentum going with the One M9. This year Samsung is changing it up dramatically, but HTC is staying the course. Let’s see how these 2015 flagships stack up.

If you’ve held one Samsung phone, you’ve held them all, right? Light, somewhat cheap-feeling, and almost entirely plastic — that was Samsung’s modus operandi before mid-2014 when it became apparent Galaxy S5 sales were coming in significantly below expectations. It began tinkering with metal frames and tweaked designs, but the Galaxy S6 is more than a tweak.

While it retains that general Samsung aesthetic, the GS6 has virtually no plastic anywhere. The front (with its 5.1-inch screen) and back are both glass, and the frame is aluminum. No more of that painted chrome plastic for Samsung’s flagship. There are two versions of the GS6, one with a regular flat screen and another with a curved panel that slopes down at the edges. I don’t see the point of this personally, but it does look kind of neat. It might be annoying in practice, though.

On the face is a physical home button flanked by capacitive multitasking and back buttons. The fingerprint reader is now a touch sensor rather than swipe-based. The GS6 does bear a striking resemblance to the iPhone 6, but you can’t blame Samsung for doing what works. Samsung did, however, do a good job of slimming down the bezels from the GS5, which always felt rather clunky to me.

Samsung’s devices have always had two notable features — a removable battery and microSD card slot. The Galaxy S6 doesn’t have either. I find this strange, especially for Samsung, but it has bumped the base model’s storage to 32GB and will offer both 64GB and 128GB (wow) versions.

The Galaxy S6 has a lot in common with the HTC One M9. The M9 too is a sealed phone just like the M8 was. The battery doesn’t come out, but there is a microSD card slot. The Galaxy S6 looks much different than its predecessor, but HTC changed very little from the M8 to the M9. Again it’s a rounded unibody aluminum frame with a 5-inch screen (more on that later) and dual front-facing Boom Sound speakers. If you see the M9 from certain angles, you might not even be able to tell it from the M8.

HTC has made a few changes in the design, as an eagle-eyed observer will note. First, the black bezel at the bottom of the front has been shrunk a touch and the top-mounted power button has moved to the side. Some of the lines on the phone are also ever so slightly different as well. Around back there’s a single large camera sensor instead of the dual cameras from the M8.

So both phones will feel very premium, but the M9 will feel about the same as last year’s model did. Samsung changed a lot to catch up in the general look and feel department.

HTC and Samsung have both stuck with identical screen sizes from last year’s flagships. The GS6 is sporting a 5.1-inch Super AMOLED panel and the M9 has a 5-inch LCD. Samsung’s screen might be the same size, but the resolution has been bumped up to 2560×1440. HTC will use 1080p for the third year in a row, probably because 1440p LCD panels are still rather mediocre.

Samsung’s quad-HD AMOLED will pack in a lot more pixels in a smaller space than other phones. It works out to a staggering 576 pixels per inch. The One M9 will again offer a “mere” 440 pixels per inch. One of those numbers is definitely larger than the other, but there are very few instances where most people will be able to notice the difference in resolution. If you’ve got less than perfect vision, those extra pixels on the GS6 might be wasted anyway.

These screens are also based on completely different technologies. Samsung makes the best AMOLED screens in the world, and it shows. The panel used on the Note 4 was devastatingly gorgeous, and the GS6 will probably look even better. Samsung has overcome many of AMOLED’s issues like low brightness and inaccurate, too-warm colors. Meanwhile, LCD is a reliable technology that offers accurate colors and good outdoor visibility. HTC tends to choose very good LCD panels too.

So, it’s likely that Samsung has a more impressive screen on its flagship device, but the battery has only grown a little to 2550mAh (2600 in the Edge variant). It should get solid battery life, but HTC’s 1080p LCD will use much less juice in most instances and it packs a larger 2840mAh cell. That should translate to much better battery life with more screen-on time for HTC.

Both of these screens have their strengths, but it’s up to you to decide what’s most important — being pretty or lasting a long time.

HTC first introduced the 4MP UltraPixel camera to the world in 2013 with the One M7. In 2014 it put out the M8 with another 4MP camera, but an additional depth sensor was added. The “Duo Camera” was mostly ignored by consumers, and this year HTC is going back to basics with a single high-resolution camera. The One M9 has a 20MP camera on the back and a 4MP UltraPixel sensor on the front.

The M9 has only just been announced, so it’s impossible to say how good the photos will be. At the very least HTC will have more to work with. At 4MP, you couldn’t crop a photo from the M8 even a little bit without seeing some blurring. It will come down to how well HTC has optimized the software and post-processing. However, one major knock against the M9 is the lack of optical image stabilization. That’s the technology that helps avoid blurriness in longer exposures from hand shaking.

Samsung has consistently been at the top of the heap when it comes to photography on Android. The hardware is almost the same across OEMs these days, but Samsung has some truly excellent software tricks that can pull above average images out of poorly lit environments. The HDR shots that come out of Samsung’s phones have also been excellent.

The Galaxy S6 will come equipped with a 16MP camera, which is the same as last year. Samsung uses phase detection to speed up focusing and promises the GS6 will be even faster than the Galaxy S5 was. It has optical image stabilization, which is good for pictures in low light and HDR. However, that makes the camera module a little thick, meaning there’s a noticeable hump on the back of the Galaxy S6.

Both these devices have the ingredients to take great pictures. HTC has a lot of ground to make up, though.

Usually, there’s very little difference on the inside of flagship phones. They’re always using the latest and greatest from Qualcomm, but this year is a bit weird. Samsung allegedly encountered overheating issues with the Snapdragon 810 during the design phase, so it ditched Qualcomm’s chip in favor of its own in-house Exynos solution. HTC, on the other hand, didn’t have many options and has opted to use the Snapdragon 810 in the M9.

Samsung’s new Exynos is still a little mysterious. Samsung usually only uses Exynos chips in the international variants of its devices, and this will be the first of its new 14nm octa-core chips. The 64-bit Exynos 7 Octa 7420 used in the Galaxy S6 (standard and Edge) has four fast Cortex-A57 cores and four low-power Cortex-A53 cores (ARM calls this configuration big.LITTLE). It uses a technology called global task scheduling to mix and match all the cores with cache coherence to pass tasks around in whatever way is deemed most efficient. This is paired with a Mali-T760 GPU, also designed by ARM.

The Snapdragon 810 in the HTC One M9 is also a 64-bit octa-core chip based on the A57 and A53 setup. Just like the Exynos, it has support for global task scheduling. On the GPU side, Qualcomm stuck with its in-house Adreno 430. So most of the pieces are the same, but early benchmarks show the Exynos chip performing better than the Snapdragon. Is that because of thermal throttling? It’s impossible to say right now, but both devices will probably be fast enough for most activities pretty much all the time.

We’re well and truly into the era of 3GB of RAM for a flagship phone, and both these devices offer it. One notable difference, Samsung opted to use LPDDR4 and HTC is still on LPDDR3. It’s not clear if this will have a noticeable effect on performance, but it’s something to keep in mind.

One of my favorite technologies of 2014 was Qualcomm Quick Charge 2.0. It goes by various names like Motorola Turbo Charging and HTC Rapid Charging. Basically, the chipset can pull as much as 15 watts of power from a compatible wall adapter and go from 0 to 60 percent in 30 minutes (with a 3000mAh battery). The HTC One M9 supports Quick Charge 2.0 because it has a Snapdragon chip. The Galaxy S6, on the other hand, has an Exynos chip. That means no Quick Charge. Samsung says it has an alternative solution in place for faster charging, but you’ll probably have to deal with Samsung’s included charger only.

The GS6 makes up for that a little with included wireless charging, which used to require replacement back on previous Galaxy phones. Since you can’t take the back off the GS6, Samsung figured it ought to just built that in. The One M9 still lacks wireless charging.

Both these phones will come with Android 5.0 Lollipop, but this won’t be the version of Lollipop Google had been rolling out on Nexus devices for the last few months. The Galaxy S6 and One M9 will have OEM skins and features baked in. In the case of Samsung that’s TouchWiz, and for HTC it’s Sense 7.

Both Samsung and HTC have come a long way in the software department. A few years ago Sense was clunky and dated, but with the One M7, HTC started to turn things around. Now its software has very clean, modern design and cool features like BlinkFeed and a new theme engine for the M9.

TouchWiz has been much maligned in the past, and still is in some corners of the internet. Samsung’s transformation of Android hasn’t always been done with as much care as it should have been, leading to unacceptable feature bloat and sluggishness. Samsung started to change that with the Galaxy S5, which removed and disabled a number of little-used features. TouchWiz also includes a few genuinely useful options like download booster and ultra power saving mode.

HTC Sense might be a little more attractive in general, but Samsung is working hard to make TouchWiz more consistent and less messy. TouchWiz on the Galaxy S6 still has morestuff in it than HTC, most of which you’ll never use.

HTC clearly thinks it has a winning formula with the One series, which is why it only made a few tweaks to the design and feature set of the One M9. HTC has addressed concerns over the camera, boosted the battery size, and moved the power button to a more convenient place. If HTC has a problem going into this year, it’s that the One M9 isn’t very exciting. You can hardly tell the difference between it and the M8.

Aside from the internals, HTC could have made this exact phone a year ago at a time when it would have beaten the pants off of the Galaxy S5. Going up against the Galaxy S6 will be much more difficult.

Samsung has taken our criticisms to heart and completely rethought how it makes phones. The Galaxy S6 has a sealed body with no microSD card slot and a non-removable battery. Certainly some longtime Samsung users will be irked by this decision, but a unibody phone feels more premium. That was Samsung’s biggest problem. You can’t charge $600 for a phone that feels like a $300 phone anymore.

The Galaxy S6 is probably the more interesting of the two simply because it’s such a departure from the past. However, these will both be excellent phones.