With smartphones, as with any category of consumer electronics, we have no choice but to accept compromises. This has been the case throughout the history of cell phones and it continues to hold true even with best handsets on the market today. Apple’s (AAPL) iPhone 5 features a class-leading design with fast, smooth software, but it has a comparatively small display and lacks some of the great new functionality we’ve seen introduced on other platforms in recent years. The Samsung (005930) Galaxy S III is a sleek handset with a stunning screen and a great feature set, but it feels like a cheap toy, as does its successor. Nokia’s (NOK) Lumia 920 packs plenty of punch in a sleek package, but it’s thick and heavy, and it is missing a boatload of top apps. It’s inevitable — some level of compromise is inherent in all smartphones.

BGR reviewed the international version of HTC’s (2498) upcoming flagship smartphone late last month. We loved it. Other early reviewers concurred; the HTC One received critical acclaim across the board.

While HTC’s success with the upcoming HTC One is anything but certain considering the stiff competition and massive marketing budgets HTC faces from rivals like Apple and Samsung, there’s a reason this new phone has been adored so widely by early reviewers. It’s not just the impeccable design. It’s not just the sleek unibody aluminum case. It’s not just the fantastic construction. It’s not just the dramatically improved Sense software suite. It’s not just the great features baked into Android 4.1.2 Jelly Bean. It’s something more than all that.

The HTC One is the closest thing we have ever seen to a no-compromise smartphone.

It this regard, the HTC One changes everything we have come to accept with smartphones, and with consumer electronics in general. You don’t have to have a cheap-feeling plastic phone like the Galaxy S III to also have a big, beautiful high-definition display. You don’t have to live without innovative features like Google Now or deal with a comparatively tiny screen to have a gorgeous piece of hardware like the iPhone 5. You don’t have to carry a huge, clunky handset like the Lumia 920 to enjoy a fresh user interface that positions real-time content updates at the forefront.

With the HTC One, you can have Apple-quality hardware, a Samsung-quality display, one of the most refined versions of Android in the world and an all-around outstanding user experience all rolled up into one single smartphone. HTC might have launched the One X+, One X, One S and other One-branded smartphones last year, but this is the first handset truly worthy of the “One” moniker.

I have been carrying the global 3G version of the HTC One for more than two weeks and now I’ve had the AT&T (T) version, the subject of this review, for the past few days. (AT&T’s version of the HTC One launches on April 19th starting at $199.99.)

First and foremost, the HTC One is a masterpiece in terms of design as well as fit and finish.

HTC has once again built a sleek and sturdy unibody aluminum case to house its new flagship phone. A plastic insert runs around the perimeter of the handset and holds things like the microUSB charging port, volume rocker, audio jack and power button. The face of the phone consists of a large sheet of Gorilla Glass that spills over the sides and maintains the lines created by the polished chamfered bezel. The aluminum enclosure extends above and below the glass on the front of the handset to cover the “BoomSound” speakers, sensors and a front-facing camera.

The back of the case on the HTC One is convex aluminum that houses a camera, an LED flash, a secondary microphone for noise cancellation, and branding.

The end result is a device that is remarkably sleek and comfortable to hold despite being quite large at 137.4 x 68.2 x 9.3 millimeters. The 9.3-millimeter dimension is deceiving though, because the sides of the phone taper in. The One is much thinner at its edges than it is at its center and doesn’t feel thick at all while being held.

It should be noted that despite having a name that HTC executives should be embarrassed ever made it to the short list of possibilities, “BoomSound” is quite fantastic. No other smartphone even approaches the sound quality achieved by the One’s speakers, integrated amplifiers and Beats Audio tuning. Seriously — if BoomSound is a 10 on a scale of 1 to 10, the next closest smartphone might rate a 3 or a 4.

Though it has the added benefit of fantastic sound quality on voice calls (call audio plays through one of the phone’s main speakers but at a much lower volume, of course) the BoomSound feature is really only good for people who watch videos or listen to music on their smartphones without headphones. I do neither on a regular basis, so BoomSound doesn’t matter much to me personally. The Beats audio tuning on sound delivered to connected headphones is far more important to me and thankfully, it’s just as impressive as it has been on earlier HTC smartphones.

The display on the HTC One is another big check in the plus column. This full HD 1080p display is absolutely gorgeous. Though it’s only one factor among many that make the One’s display so good, the pixel density on this panel tops both the iPhone 5 (326 ppi) and the Galaxy S4 (441 ppi) at 468 pixels per inch.

Images and text are both very crisp and sharp on the 4.7-inch screen, and the contrast is more than adequate. I find that colors aren’t quite as vivid as they are on the Galaxy S4 or iPhone 5, but the result is actually a bit more natural looking to my eye — colors on the Galaxy S4 are so vibrant that they seem exaggerated, and this is the case to a lesser degree on the iPhone 5 as well.

Moving from the sleek exterior and impressive display to the software, HTC Sense and its new bells and whistles will likely still be polarizing. Purists will complain that Sense detracts from the Android experience while HTC fans will argue that Sense enhances it. As is often the case, reality lies somewhere in the middle.

The latest version of Sense is the most refined iteration yet, and it could potentially sway a number of users who were unhappy with older versions.

Much of Android fans’ animosity toward Sense seems to stem from early versions of the software, which were slow and clunky. This is no longer the case. Advancements in component technology and improvements to HTC’s code now yield a user experience that is entirely free of freezing, stuttering and bogging. Scrolling is smooth, apps refresh with new data quickly and the look of the interface is much cleaner and more intuitive than it has been in the past.

A few things about HTC’s software that I find particularly impressive:

The user interface: I have always liked the Sense interface to an extent, and I have found that it gets better with each new iteration. In its latest form, Sense is much less cumbersome than it has ever been, though it still comes together as a significant overhaul to the Android UI. I find many aspects of Sense to be improvements over stock Android and clean, gorgeous widgets continue to take center stage.

In terms of apps and software tweaks, HTC’s additions are hit or miss. I consider HTC’s latest email app to be among the best there is, for example, and there are other HTC-built apps I enjoy as well. But on the flip side, there are still some things that are terribly annoying.

A quick example: to create an app shortcut on a home screen, you now must long-tap on an icon in the app menu until it detaches, drag it all the way up to the top left corner and hover over the “shortcut” indicator, and then without letting go, you have to drag it back down and move side to side between home screens until you find the spot you want. This is a huge step backwards compared to Android’s stock behavior and there are a number of similar idiosyncracies in Sense.

BlinkFeed: HTC’s “BlinkFeed” is an active home screen that aggregates content from as many as 1,400 different providers. It also mixes in content from social networks like Facebook, Twitter and LinkedIn. Updates can be downloaded automatically on a set schedule or BlinkFeed can be refreshed manually, and the design is very clean and slick.

BlinkFeed is a great feature for people who always want to stay connected, and HTC’s implementation is impressive. But it’s not for everyone. For people like me who don’t want to be bothered with social network updates or news on their home screens, you can set up normal HTC/Android home screens that are packed with as many standard app icons and widgets as you want. Then BlinkFeed only comes into play when you swipe over to the left-most home screen.

HTC TV: HTC’s TV app is without question one of my favorite features on the HTC One.

Powered by personalized TV guide provider Peel, HTC TV is a cross between an interactive channel guide and a universal remote control. Shows and movies are represented by thumbnails and simply tapping on the thumbnail of a program lets you set a reminder to watch it once it comes on. If you tap on a show or movie that is currently airing, the One will tune your cable or satellite box to the appropriate channel.

How is that possible? The One’s power button is also an IR blaster capable of controlling any home entertainment device — TVs, receivers, Blu-ray players, DVD players, cable boxes, satellite boxes, DVRs and even these weird old things called VCRs. If it uses a standard IR remote, the One can control it.

HTC TV also lets users mark shows and movies as favorites so they’ll appear at the top of the list any time they’re airing or coming up. This is a great feature, but I wish I could also hide shows I don’t like. I’m sure there are plenty of people out there who enjoy “Cougar Town” and “Say Yes to the Dress,” but I’m not one of them so there’s no reason these shows should appear on my guide.

The app features a universal remote function that you set up by room, so you have one set of controls while watching TV in your living room and another set while watching in your bedroom. And since having to unlock your phone every time you want to change the channel would be a pain, the One can be set to automatically illuminate the display every time you pick it up when the HTC TV app is left open.

This is a huge step toward achieving what the modern TV-watching experience should be. I shouldn’t have to flip around or scroll through an endless sequential channel guide to see what’s on. The device I use to control my TV should know what shows and movies I like, show them to me in a logical way with a beautiful UI, and help me discover great new content. HTC and Peel don’t really have the discovery part down yet on the One, but I have a feeling they’ll get there soon enough.

Similar solutions are currently available on some tablets, but having this app on a smartphone that users carry with them at all times is far more convenient.

Of course, the HTC One certainly isn’t perfect — though finding faults isn’t as easy with the One as it is with most other phones.

For one thing, this is a big phone. For some, it will be too big. For others, it will be fine. I personally fall somewhere in the middle.

The One is a bit larger than I would like it to be, but the size isn’t a deal breaker for me. The display size means the phone borders on “phablet” territory, depending on your definition — market research firm ABI defines a phablet as a smartphone with a display that measures between 4.6 and 5.5 inches diagonally — but it’s far more manageable than phones like the Galaxy Note II.

Until we start to see handsets with true edge to edge displays, my ideal screen size is about 4.3 inches. This size lets users with average sized hands operate the phone comfortably with one hand, but it also provides plenty of canvas for apps, images and videos. Handsets like the One with bigger displays will require fumbling and awkward stretching for most people when being used with one hand.

Battery life is good but it could be even better with more thorough power controls. The One has a “Sleep Mode” function that automatically turns off the device’s data connection during “long periods of inactivity,” but a more comprehensive solution like Motorola’s Smart Settings feature would offer additional battery life benefits.

I would also like to see HTC introduce other features available in something like Smart Settings. Automatic time-based and location-based triggers can be added using third-party apps, but their utility and user experience would be dramatically improved with tighter OS integration.

In my time with the One, I found that I was able to go a full day between charges with no problem on the global 3G model, with average and even borderline-heavy use. A typical day might include obscene amounts of email, constant checking of Twitter and Google Reader, some voice calling, some navigation, some music streaming, some web browsing and an hour or so spent with HTC TV.

I can’t say much about the battery performance of the AT&T model with LTE yet, because HTC only delivered units to reviewers last Thursday (four days ago). In that short time span though, I haven’t noticed much of a hit compared to the global model. Expect to charge it once each day unless you’re streaming video over LTE for long periods of time or performing other heavy tasks like playing games.

I can say, though, that any hit the phone takes in terms of battery life is certainly worth it — I was hurting without AT&T’s LTE service, which in my area averages around 17Mbps to 20Mbps down and 13Mbps to 15Mbps up.

The HTC One’s camera is very interesting.

HTC decided to stop fighting the megapixel war and introduce new “UltraPixel” technology that the company claims produces higher quality images despite fewer megapixels (4 megapixels, to be precise). You can read all the marketing verbiage and technical jargon on HTC’s site. In practice, I found that photos captured with the One are good, but not great.

Low-light performance outshines most competitors, without question. HTC’s optics let in more light and the result is better pictures in dark environments. But I found that photos captured in normal lighting conditions were not as clear and sharp as they are with other leading camera phones like the Lumia 920 or the iPhone 5. In fact, I think the photo clarity might be a bit better on previous-generation HTC phones like the One X+.

The camera software is quite impressive though, packed full of features but easy to navigate. There are also some added bonuses, such as the ability to quickly capture a series of sequential photos and choose the best one, built-in filters a la Instagram, a function that can eliminate unwanted items from photos after they are taken, and HTC Zoe.

HTC Zoe is a bit of a gimmick but it’s very impressive before the novelty wears off. In the few weeks I’ve had the One, every single person I’ve shown this feature to has been wowed.

Zoe takes various photos and videos shot while the feature is enabled and combines them automatically into a movie complete with a musical score. These movies are created almost instantly without any intervention from the user, though they can be edited manually if, for example, he or she wants to change the music or make other edits.

When it comes to Android, apps are still a big barrier for me and this remains true with the One.

I almost always carry an Android phone with me these days, but the iPhone is still my primary handset for both personal use and for work. There are a number of reasons I use an iPhone and apps sit somewhere near the top of my list.

Apart from proprietary apps and services like iMessage, which I use to communicate with almost all of my friends and family, most of the apps I rely on regularly are now available on the Android platform. Apps that aren’t, such as TweetBot and Reeder, have comparable Android alternatives. But I find that even the best apps available for Android aren’t as smooth and refined as they are on iOS.

Perhaps Android developers are given too many liberties and too few guidelines or perhaps Google’s (GOOG) SDK is somehow limiting. I can’t say. What I can say is that well-made iOS apps always seem to outshine their Android counterparts and provide an all-around smoother and cleaner user experience.

TweetBot, the iOS Twitter client I mentioned earlier, is a great example. I use a fantastic Twitter client called Falcon Pro on Android devices and I can’t say enough good things about it. It’s well designed, the interface makes great use of panels, it has great Twitter list support (which is very important to me), and it’s reasonably fast. But TweetBot has an even better UI, lists are even more accessible, and it’s much faster and smoother than Falcon Pro. Unfortunately, this is all too common when comparing similar apps on the two platforms.

Another example mentioned earlier was Reeder, an iOS app I use for mobile access to Google Reader. I have tried a dozen RSS readers for Android and landed on an app called gReader that I very much enjoy. As great as it is, however, its user interface nowhere near as clean as Reeder, performance isn’t as smooth, and it has eight pages of settings that are beyond overcomplicated.

I’m confident that this will change over time. But right now, it’s an unavoidable issue for those who seek the smoothest possible user experience.

And speaking of apps, it should be noted that AT&T’s version of the One ships with a bunch of standard AT&T Android apps many would consider bloatware. It took me all of 15 seconds to stuff them all into a folder never to be seen again, and the base One model includes 32GB of storage so there’s plenty of room left for apps, videos, images and other data.

Lastly, I’m not sure who decided to put the power/lock button on the left side of the handset instead of the right side, but I sincerely wish he or she hadn’t. It makes locking the screen impossible with one hand (unless you’re left handed) and it is incredibly annoying (unless you’re left handed).

The HTC One comes at a time when HTC desperately needs a hit. Very, very desperately. The company’s market share and performance continue to slide as Apple and Samsung dominate the smartphone market, and Samsung’s next-generation flagship phone is about to launch globally with support from carriers in 155 countries and billions of marketing dollars.

HTC doesn’t have billions to dump into marketing. It also doesn’t have the momentum the Samsung has, coming off a worldwide smash in the Galaxy S III. What HTC does have, however, is one of the best smartphones the world has ever seen.

The One combines an impeccable design, a sleek aluminum body, sturdy construction, well-made software and a handful of innovative features into a single package that is class-leading in almost every regard. The fit and finish are outstanding and the latest version of Sense is elegant and smooth. And just to help illustrate just how sturdy this phone’s build really is, I dropped it twice so far while it has been in my possession. The first time it slipped out of my hand and tumbled down a flight of carpeted stairs onto my hardwood living room floor. The second spill saw the phone slide out of a sweater pocket and fall glass-first onto the tile floor in my kitchen, resulting in one of the loudest, scariest sounds I have even heard a gadget make. The One emerged from both spills without a scratch.

A single smartphone is not going to reverse HTC’s fortunes. The competition is too fierce and HTC’s current slump is far too severe. But with the right combination of marketing, significant carrier support and a little luck, the One could very well be a turning point for HTC.

With the Galaxy S4, Galaxy Note III, Google’s “X Phone,” new RAZR handsets, a new flagship Optimus G and plenty more due to launch this year, competition at the high end of the smartphone market will be more fierce than ever before. But unless something truly unexpected pops up, the HTC One will almost certainly be the best all-around Android phone to launch in 2013. The One includes all of the features that make a hit and none of the big compromises we’re typically forced to accept, and in that regard it changes everything.