Which phone should you buy?

Editor's Note:This story originally published September 14, 2012, and updates often to reflect the arrival of new phones.

"Which phone should I buy?" This is the single most common question readers like you ask phone reviewers like us every day. We get it, it can be a challenge, especially with superb devices such as the Samsung Galaxy S5, HTC One M8, iPhone 5S, and Nokia Lumia Icon. But depending on your price range and what's available where you live, the phone you should be getting may not be a flagship -- it could turn out to be the Nokia Lumia 520/521 or iPhone 5C.

On the bright side, options are a good thing -- if you're armed with the knowledge necessary to make smart shopping decisions. Sit tight as we lay out what you need to know to find the right mobile platform and model for you.

Which operating system is for you?

Android, iOS, and Windows Phone. Each has its pros and cons, depending on what you want. A crave-worthy phone design might lure you to a new OS, but most people we know prefer to start with the platform and go from there.

iOS

Apple's iOS has a well-integrated ecosystem, a very full apps marketplace, and a fairly intuitive interface, but you're pretty much locked into iTunes for content. If you already have a Mac, an iPad, and/or an iPod, it's probably easiest to go with an iPhone.

iPhones have the advantage of receiving the same OS upgrade at the same time, and the newest OS is usually available on multiple devices. iOS 7, for instance, will work on the iPhone 5S, 5C, 5, 4S, and 4 but not on the iPhone 3GS or earlier.

Android

For its part, Android is the most customizable OS and a wonderland for tinkerers. However, most manufacturers and carriers add a specialized twist, which can lead to slower OS updates, and to an interface that may require a little more ramping-up to do straight out of the box. On the other hand, phone-makers can use that custom layer to add a lot of software features that others just don't have.

True Android devotees should spring for the latest Google Nexus handset, or a Google Play Edition of a flagship phone.

Windows Phone

Then there's Windows Phone. Microsoft's OS has a simple, appealing interface, and Windows Phone 8.1 helps level the playing field with the Cortana voice assistant and a notifications center. Power users still may not find it quite as deep or as flexible as Android, and its app ecosystem isn't as robust. Still, excellent hardware choices give Windows Phone a lift, and it has strong integration with Office and Microsoft's other services.

Best iPhone: In the easiest pick of this entire list, choose the iPhone 5S.

Best Android phones: Samsung Galaxy S5, HTC One M8, Samsung Galaxy Note 3, LG G Pro 2.

Best Windows phone: Nokia Lumia Icon (Verizon), Nokia Lumia 1520 (AT&T).

Do you shop by phone or by carrier?

It used to be that if you were happy with your carrier, or were within an upgrade window, you'll probably pick from your carrier's choices of phones. And if you were off-contract or in between contract cycles, you'd be more likely follow a particularly compelling phone.

Things are a little different now, with T-Mobile joining the off-contract ranks and spurring other US carriers to slacken their vice grips on the 2-year contract structure (and 3 in Canada) with a whole heap of upgrade and payment options.

Then there's the question of the phones themselves. The practice of selling interesting devices exclusively with a single carrier have shriveled, and today, providers large and small stock the most desirable handsets. I still think the people who wind up sticking with their carrier long-term should choose from among those options, but there are other things you have to consider, too, like which carrier covers your area best.

Remember that phones sold through a contract appear cheaper because they're subsidized -- you pay less up front to your carrier in exchange for paying a higher monthly rate. These providers also typically have the widest coverage and offer the widest range of premium phones.

However, every national carrier also has a prepaid option. T-Mobile is completely no-contract, as is its subsidiary, MetroPCS. AT&T's Aio Wireless complements the company's own small range of simple prepaid phones. Verizon lets you buy nearly any phone at retail value and then pay month-to-month, and Sprint manages prepaid options through its Virgin Mobile and Boost Mobile brands.

Depending on how you use your phone, a prepaid service could work out to be cheaper over time. You also won't have to worry about breaking your contract and paying a fee.

Several prepaid carriers operate on their own networks as well, like U.S. Cellular and Cricket Wireless, which also leans on Sprint's network through a partnership. These providers have regional footprints and are sometimes slower to adopt premium phones and improve on their technology. Cricket is slowly building up 4G along with its roster of top phones and provides a unique music service.

Voice and data coverage are also key. There are carrier maps you can look at to see roughly if your area is taken care of, but asking neighbors is usually more reliable. All carriers are still rolling out 4G LTE networks, but Verizon is far ahead of the others. Sprint has the smallest number of LTE markets of the major nationals, but is pushing its next-generation network, called Spark.

The carrier's pricing structure is also something to think about, though it's gotten even more confusing for customers considering early upgrade options, and pooled data plans versus individual rates.

Favorite AT&T phones: Samsung Galaxy S5, HTC One M8, iPhone 5S, Nokia Lumia 1520, Samsung Galaxy Note 3.

Favorite Aio Wireless phones: iPhone 5S, iPhone 5C, Samsung Galaxy S4, Nokia Lumia 520, Motorola Moto G.

Favorite Boost Mobile phones: iPhone 5S, iPhone 5C, Boost Max, LG Optimus F7.

Favorite Cricket Wireless phones: iPhone 5S, iPhone 5C, Samsung Galaxy S4.

Favorite MetroPCS phones: Samsung Galaxy S5, Samsung Galaxy Mega, Nokia Lumia 521, LG Optimus F6.

Favorite Sprint phones: Samsung Galaxy S5, HTC One M8 Harman Kardon, iPhone 5S, Samsung Galaxy Note 3.

Favorite T-Mobile phones: Samsung Galaxy S5, HTC One M8, Apple iPhone 5S, Google Nexus 5, Samsung Galaxy Note 3.

Favorite U.S. Cellular phones: Samsung Galaxy S5, iPhone 5S, iPhone 5C, Samsung Galaxy Note 3, Samsung Galaxy Mega.

Favorite Verizon phones: Motorola Droid Maxx, Samsung Galaxy S5, HTC One M8, iPhone 5S, Samsung Galaxy Note 3, Nokia Lumia Icon.

Favorite Virgin Mobile phones: iPhone 5S, iPhone 5C, Samsung Galaxy S3, HTC Desire 601.

Which experience: Premium or functional?

One big question to ask yourself when choosing a mobile phone is how you plan to use it. Is it your camera, your gaming center, e-book reader, streaming radio, or portable multimedia storage device? If the answer is yes to one of these or more, then you're looking at a premium smartphone.

The cream of the crop will usually have a big, high-definition screen, larger storage capacities, a higher-resolution camera, longer battery life, and a faster processor. Power doesn't come cheap, since top-tier smartphones typically run anywhere from $200 to $300 on contract and between $500 and $700 off-contract, though there are promotional deals at every turn.

As nice as the premium smartphones are, for some people, they're just overkill. The benefit of these smartphone operating systems is that they generally spread their software power to handsets of all shapes and sizes, which means that hardware capabilities are often the only thing that separates the top from middle from basic tiers.

If you're less picky about having the best of the best, you could walk away with a smartphone that runs all the same apps as the big boys for half the price. These phones typically cost between $0 to $150 on contract and in the $200 to $500 range off-contract, depending on the carrier and the promotional deal of the moment. Phones from previous years are also dramatically less expensive.

For those looking only to text or make calls, carriers do still offer messaging phones (a few with keyboards) and simple phones (many with a flip design). These phones might seem pricier than you'd expect because the carrier isn't helping subsidize the cost, but the upside is that you won't have to fork over money for a pricey data plan each month. You can find simple phones for between $15 and $80. Check out your best bets here.

Best high-end phones, period: Samsung Galaxy S5, HTC One M8, iPhone 5S, Nokia Lumia Icon, Nokia Lumia 1520, Samsung Galaxy Note 3, Motorola Droid Maxx.

Best midrange phones (on-contract): Samsung Galaxy S4, iPhone 5, HTC One, Motorola Moto X, Nokia Lumia 520/521, LG Optimus G Pro (AT&T), HTC One Mini.

Best midrange phones (off-contract): Samsung Galaxy S4, iPhone 5C, Google Nexus 5, Lumia 520/521, LG Optimus F3Q (T-Mobile).

Design: Blend in or stand out?

A phone is such a deeply personal product, you might find yourself strongly drawn to one style or another. If you prefer a low-profile phone, good news. Most are black or dark-gray shingles, though white and light gold have become popular color choices. Others come in edgier colors like red, cyan, and yellow, or with distinct shapes, corners, and backings.

The HTC One M8 has surround speakers, a gorgeous all-metal body, and a comfortably rounded backing. Nokia's phones are known for flaunting numerous, and wild colors. We still love the elegant, industrial design of the iPhone 5S, especially in gold, as well as the brighter colors of the iPhone 5C. We also enjoy the personal flair you can put into Motorola's Moto X backplates.

Favorite stylish phones: HTC One M8, iPhone 5S, iPhone 5C, Motorola Moto X, Motorola Droid Maxx, Sony Xperia Z1S.

Do you like a large, medium, or small screen?

A phone's single most important physical element is its screen. Up until recently, you'd find the largest screens within the Android camp, the most massive one available belonging to the tabletlike Samsung Galaxy Mega, which features a whopping 6.3-inch display. Now, the Nokia Lumia 1520 has entered the mix with its 6-inch LCD, easily the largest Windows Phone handset yet. HTC has also jumped into the gargantuan phone arena too. Its One Max pushes the company's signature metallic design to staggering proportions. Our favorite phablet though is the Samsung Galaxy Note 3 which boasts an excellent 5.7-inch OLED screen that's sharp, colorful, and has extremely high contrast. (Check out supersize phones here.)

The Samsung Galaxy S5, Nokia Lumia Icon, LG Optimus G Pro, and HTC One M8 also offer outstanding viewing with high-resolution displays in the 5-inch range. As you can imagine, looking at everything from Web pages and photos to movies on these devices is an awesome experience.

Still, others prefer a smaller device that's more pocketable. There are fewer of those to choose from than in years past -- mostly in the middle tier. There's the medium-size Motorola Moto X with an edge-to-edge display that, despite its slim, compact chassis, features a vibrant 4.8-inch screen.

Those with small hands or seriously tight pockets aren't going to find a lot of options that match to high-end specs inside.

Best "small" (4 to 4.4 inches) phones: iPhone 5S, iPhone 5C.

Best "medium" (4.5 to 4.9 inches) phone: Motorola Moto X, HTC One Mini, Samsung Galaxy S4 Mini.

Best "large" (4.7 to 6 inches) phones: Samsung Galaxy Note 3, Samsung Galaxy S5, HTC One M8, Motorola Droid Maxx.

How often will you use the camera?

If you're like us, your smartphone camera has become your primary shooter for casual, day-to-day moments. It's also a chief selling point for any phone.

Nokia, Samsung, Apple, and HTC are our go-to manufacturers for smartphone cameras, not quite in that order. Nokia's Icon and 1520 kill it with low-light performance. Samsung's 16-megapixel shooter in the Galaxy S5 also takes some consistently great shots, even in automatic mode.

The iPhone 5S camera is also at the top of the class, and pumps out consistently good photos in macro and low-light scenarios without you having to fuss with settings. It also packs a panoramic mode with 28-megapixel resolution.

HTC's "ultrapixel" camera takes photos with alarming speed, but isn't quite as detail-rich, and is the weakest of the three when it comes to blowing out backgrounds. Check out our photo comparison of the HTC One M8, Samsung Galaxy S5, and iPhone 5S.

Best camera phones today: Apple iPhone 5S, Nokia Lumia 1020 (AT&T), Samsung Galaxy S5, HTC One M8, Nokia Lumia Icon.

How fast a phone do you want?

The mobile phone arms race is as hot as ever, and much as with desktop computers of old, manufacturers constantly vie for performance bragging rights. Similarly, elite smartphone shoppers pore over spec sheets and feature lists in a quest for the ultimate handset.

Apple has introduced its 64-bit A7 processor, which doubles the speed of the previous A6. Samsung's GS5 goes quad-core in the US, and other powerful Android and Windows Phone handsets still by-and-large use Qualcomm's quad-core Snapdragon processors.

Honestly, though, a phone's clock speed is a relative value. A slower CPU can make efficient software fly while the opposite is true of a handset weighed down with useless apps.

Blazing quad-core specimens: Samsung Galaxy S5, HTC One M8, iPhone 5S, Nokia Lumia 1520.

Will you use your phone for calls?

These days, calls are often the last thing on a phone owner's mind, but if you care about talking in addition to your texts, games, and emails, you have a bit of a chore ahead.

Unfortunately, call quality is the hardest attribute to consistently pin down, since it vacillates so widely based on network strength in your location, your building, and even the time of day. We test call quality in each phone review, but what's good for us at the CNET offices in San Francisco or New York might be terrible in your neighborhood.

Our best advice is to make a test call from a retail location (even if you're buying online) to check the call quality, and to ask your neighbors for an assessment. Some people still write us saying they can't get reception in their signal-blocking homes, but they can get it on the street.

How critical is long battery life?

Even the most high-octane superphone becomes a fancy paperweight when it runs out of juice. Compounding the problem are the swelling screen sizes and multiplying processing cores cropping up in modern CPU chips. Then there are 4G LTE radios that suck down data at lightning speed, but if abused, will soak up electricity like a gaggle of thirsty vampires.

That said, a few handsets manage to sagely balance their energy consumption with swift performance. Other devices are also equipped with large-capacity batteries of 2,300mAh or more, providing a deep reservoir to draw from.

Phones with superior battery life: Motorola Droid Maxx (Verizon), Kyocera DuraPlus (Sprint), Samsung Galaxy S5.

The keyboard question

Now that BlackBerry is back with the Q10, people who aren't ready to break their physical keyboard habit have another option from the best in the business.

Yet, if BlackBerry OS isn't your cup of tea, things get tricky. The number of smartphones with actual keyboards is rapidly shrinking, and there's no iOS or Windows Phone device that's QWERTY-equipped. Even worse, many phones that do fall into this category come with shoddily constructed keyboards and painful ergonomics. That said, there are some modern keyboard phones we think are worthy of recommendation. Here are our top picks for devices that provide a pleasant typing experience.

Phones with great keyboards: BlackBerry Q10, Motorola Photon Q 4G LTE (Sprint), Motorola Droid 4 (Verizon).

Final tips

In the end, whether you choose the newest thing or pick something more practical, we recommend two more tips to keep in mind. First, keep an eye out for seasonal deals, especially if you're buying phones for the family. Also, carriers love to suddenly offer special (often Web-only) discounts, typically around holiday weekends.

Second, it's a good idea to know how much time you have to return a phone without penalty, just in case you need to switch devices after your initial buy. Carriers usually offer a 14- to 30-day return window, though you may have to pay for calls and data usage during that time.