Knowing the best smartphone you can buy right now is more than just a hunch for us. We test out the latest and - sometimes - greatest cell phones in comprehensive reviews.

To properly drill down to a list of our 10 favorites in the US, we based the rankings on a lot of geeked-out factors including hardware design, performance, battery life and camera quality.

Sure, your personal preference among iOS 8, Android Lollipop and Windows Phone 8 could sway you to another device besides our top-ranked phone.

Likewise, carrier availability via AT&T, Verizon, Sprint and T-Mobile is an outlier. The best phone for AT&T may not be available on-contract through Verizon and vice-versa.

But that's why we have more than just a No. 1 pick, which, spoiler alert, isn't Apple's iPhone 6 or iPhone 6 Plus. We're not that predictable.

Before you get locked into a two-year contract or spring for that expensive unlocked, SIM-free smartphone, consult our best of guide, updated regularly.

best smartphones in the US

10. OnePlus One

OnePlus One was the surprise smartphone of 2014 thanks to the Chinese manufacturer that no one had ever heard of before this year. It's fast, large and, importantly, inexpensive.

Labeled a "flagship killer," this debut device from OnePlus has a super-customisable software that's a variant of the popular CyanogenMod, and it's backed up by powerful specs.

That includes a 5.5-inch 1080p display, a 2.5 GHz quad-core Snapdragon 801 processor, 3GB of LPDDR3 RAM and a healthy 3100 mAh Li-Po.

There's no microSD card slot or removable battery, and the 13-megapixel camera quality finishes in the middle of the pack with the same "pretty good" sensor as the new Nexus 6.

That's okay. At $300 unlocked, it's more than half of the starting price of Google's new 6-inch smartphone that is a more serious $650 without a contract.

Our only reservations are the pesky OnePlus One "invites" since it's not available through normal US carriers, and the fact that OnePlus One may equal One Plus Two in 2015.

Quick verdict

We love the fact that a new contender can maintain such a high place in the ranking of the best phones in the world - it means that it's not just a case of 'big budget means best phone'.

We were debating whether the OnePlus One could even have gone higher, but there's one big problem that you'll have if you want to get your hands on one: they're impossible to find.

Numbers won't ramp up for a while, and probably never to the level of availability of the better-known names.

But if you want a phone that offers supreme power at a really low cost: the OnePlus One is it. It's what the Nexus range used to be, and if Google ditches that program, then thankfully OnePlus has shown there will be brands to pick up the slack.