Now that the big smartphone makers have solved most of the “big-enough, fast-enough, easy-enough” hurdles for consumers, there’s lots of room for less well-known manufacturers to compete by selling full-featured phones at low prices.

A great example is OnePlus, a Chinese manufacturer whose latest model, the OnePlus 3, is creating quite a stir in the burgeoning unlocked-smartphone market. 

The appeal of unlocked phones is that you can change phone service as quickly and as easily as you can swap out a provider's SIM cards. The OnePlus 3 works on the GSM standard, so you can use it with AT&T, T-Mobile, and lmany smaller providers such as Consumer Cellular.

The OnePlus 3's sleek, matte-finished aluminum unibody is just 6 inches x 3 inches x 0.3 inches, making it one of the thinnest and sleekest smartphones we’ve seen—even after you slip on one of the optional faux-wood protective covers.

It has a big, decent-looking 5.5-inch 1080p AMOLED display. Other specs are worth listing just because they are unusually appealing for an unlocked model. These include:
• a USB Type-C port for data transfers and charging;
• a speedy 2.2 GHz Snapdragon 820 processor;
• a hefty 6 GB of RAM'
• an ample 64 GB of storage; and
• a generous 3,000 mAh battery that's supposed to be able to replenish 60 percent of its charge in about 30 minutes.

You can feel confident comparing the OnePlus 3 to flagship models from the big players in the smartphone market, including Apple and Samsung.

The OnePlus 3 has a suggested retail price of $400, but it is selling for around $150 more than that on Amazon. (Buyers of the first 30,000 handsets got a Loop VR headset; that deal is long gone.) Despite the price premium, the OnePlus 3 is still a bargain.

Here are more details.

Why We Like the OnePlus 3

Built for work or travel. The OnePlus 3’s dual-SIM-card slot allows you to handle two phone numbers, even from different providers. That makes it an excellent option for anyone who needs a second smartphone for travel or business use but only has the budget—or pockets—for one device. Call logs and texts from both accounts can be conveniently viewed on one screen. You can choose which SIM to use for calls and messages, or set the phone to ask first. You have a similar level of control with various apps.

Smart cameras, front and back. Like virtually all smartphone makers, OnePlus claims its cameras have amazing powers for capturing true-to-life images. I’ll leave that judgment to our image experts, who are testing the OnePlus 3’s 16-megapixel rear camera right now. But the fact that the camera has a fair amount of resolution as well as Optical Image Stabilization does improve its chances of snapping good still images. One sort-of-nifty feature: Smile Capture, which is supposed to let you take a photo with the front-facing 8-megapixel camera just by smiling. It worked only sporadically for me. Perhaps I should check in with my dentist.

Fast and cool while charging. Smartphones typically heat up while they're charging, but the OnePlus 3 seemd to stay noticeably cool. According to the manufacturer that is due to a feature called Dash Charge.

The company says it has shifted more of the burden of power management from inside the phone out to the charger, which supplies power at lower voltages than some other rapid chargers (5V vs. 9V) while raising amperage (4A vs. 2A). This technology is coupled with what the company describes as unique temperature-regulating systems on both the phone and charger.

Dash Charge is supposed to keep the phone's performance up, as well. OnePlus says that when a phone gets warmer during charging, it throttles down processing activity to prevent overheating—that's something that other phone experts have also told me over the years. It could mean that phones tend to be less responsive when they are plugged in. According to OnePlus, Dash Charge ensures that you can play processor-intensive games at full speed even when the phone is plugged in. I didn’t notice the promised speed benefits during my informal trials, though the phone seems plenty speedy as is, probably thanks to its powerful processor and hefty RAM.

Sensible interface. One of the things that’s simultaneously good and bad about Android smartphones is that Google gives manufacturers lots of opportunities to make their own decisions with graphics and even capabilities. Sometimes that produces frustrating gimmicks. But this phone’s OxygenOS interface, which sits over Android Marshmallow, is actually pretty clean, with some unique touches that are rather useful.

These include a customizable page called Shelf that lets you add things like your favorite widgets, reminders, apps, important contacts, and frequently changed controls. Think of it as your spare home screen. One small nuisance is that the symbols for both the Back and Recent are dots; the only way to knowing which one to push is to rely on your memory.

Decent display. The OnePlus 3’s HD AMOLED display, which we are now evaluating, seemed okay. Its 1080P resolution promises more than 400 pixels per inch of resolution. And, indeed, the text on documents and web pages appeared adequately crisp in my casual use of this phone. However, the display is a bit dark and more of a challenge to read in sunlight, at least when compared to that of a Samsung Galaxy S smartphone or an iPhone.

Good connections. Some unlocked phones that we've tested recently, such as the Blu Vivo 5, cut some corners when it comes to wireless connections. In particular, they skip support for NFC, which is needed for mobile payments, or for 5-GHz WiFi connections. They also leave out support for some LTE frequency bands, which could compromise coverage in certain areas. In contrast, the makers of the OnePlus 3 say the phone supports NFC, the 802.11ac WiFi standard, and quite a few 4G LTE bands.

We’ll have more on the OnePlus 3 when it hits our smartphone Ratings.

Copyright © 2005-2016 Consumers Union of U.S., Inc. No reproduction, in whole or in part, without written permission. Consumer Reports has no relationship with any advertisers on this site.