OnePlus One, $299, www.oneplus.net

For years, the tech industry has been waiting on a unicorn device: a great, low-priced smartphone.

Many of today's high-end smartphones cost upward of $650, though much of that is hidden inside a carrier plan. You generally pay $200 or so when you sign up for the phone, and then pay the rest over the course of your contract. Still, the full price is nothing to sneeze at. If you keep your new iPhone 6 or Samsung Galaxy S5 for two years, you are looking at a minimum of $27 a month just for the device.

Well, a unicorn just galloped onto the horizon. This month, OnePlus, a start-up based in Shenzhen, China, will begin taking preorders for the One, a fantastic low-price phone that tech enthusiasts across the globe have been lusting after for months.

The One has a beautifully spare design, it's loaded with the latest tech specs, and it runs CyanogenMod, a version of Google's Android operating system that is far more flexible and easier to use than the cumbersome flavors of Android now stuffed into rival phones.

Best of all, the One sells for $299. That's not $299 with a carrier plan or some other commitment. That's $299 total, or less than half the price of a top-tier phone from Apple, Samsung or HTC. After you pay that price, you own the phone. If you take it to a carrier like T-Mobile, which offers a discount on your cellular plan if you bring your own phone, you can end up saving a substantial bit of cash in the long run.

And yet, the One is not going to work for most people — yet. That's because it comes with many caveats and warnings. Among them: You will have a devilishly difficult time getting customer service for your phone, including getting it repaired if something goes wrong.

Additionally, OnePlus' future is far from assured in a landscape of technology giants — and that future matters to the longevity of your phone. If your iPhone breaks, you can always go back to the store to get it fixed. And if you want to get rid of it, there will always be a large, willing market to take it off your hands. Isn't that certainty worth the extra coin?

For many users, that will be true; the $650 smartphone isn't going away tomorrow. Still, if OnePlus can navigate the perils of the cutthroat smartphone business, it may be giving us a peek of the glorious future of great, cheap phones.

NEW YORK TIMES