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The OnePlus 6T has been officially announced and here's our review.

Speaking in his native Mandarin, OnePlus' founder and CEO Pete Lau exudes a reserved persona, despite being only weeks away from unveiling the OnePlus 6T phone. Compared to the company's other founder, Carl Pei, Lau carries himself more formally. Though the two look unassuming in their own ways, Pei is often seen wearing cotton tees and clapping back on Twitter about free phone handouts and false product rumors. Meanwhile Lau, who is 14 years Pei's senior, mostly tweets about OnePlus industry news.

It's this calm demeanor that betrays his nervousness inside -- something you wouldn't notice until Lau explicitly mentioned it when asked about the launch.

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"My feelings are, to best summarize, complex," said Lau through an interpreter. "It's a mix of both excitement and anxiety." Donning a black button-up and bespeckled navy blazer, he goes on to compare his feelings to when your own child is about to be born.

Though the OnePlus 6T isn't out yet, we already know a fair bit about the upcoming phone. And unlike the previous years of "T-devices" (which are seen as half-step updates to the counterpart phones before it, like the OnePlus 3T over the 3), the OnePlus 6T is shaping up to be dramatically different than its OnePlus 6 predecessor.

For starters, the phone may finally achieve mainstream recognition in the US by launching with T-Mobile, which is the company's first US carrier deal. It also won't have a headphone jack -- a possibly contentious move for Android users, who have fewer and fewer options for marquee phones that have headphone ports. Finally, the OnePlus 6T beats out two established players, Apple and Samsung, by delivering an in-screen fingerprint sensor to a wide US audience.

Add on the fact that OnePlus is launching in October -- a month earlier than usual -- and it's easy to understand why Lau's feeling eager.

Goodbye to the headphone jack

Lau plays a hands-on role in the development of OnePlus's products. He's an engineer at heart, having worked at the Chinese device maker Oppo for 15 years. (Oppo and OnePlus share the same parent company, BBK Electronics.)

But as the CEO of OnePlus since founding it in 2013, he sees himself as the product manager of all product managers at the company. He knows he has to make the tough calls. That includes following a trend popularized first by Apple and later Google in lopping off the headphone jack on the 6T.

"This has been one of the most difficult decisions for us to make," said Lau. "The most difficult task in the day-to-day is… finding a balance in what's ultimately going to be part of the end product and what has to be said 'No' to."

Enlarge Image Screenshot by Lynn La/CNET

One of the reasons OnePlus cut the headphone jack was to make room for the in-screen fingerprint sensor, which the company brands as Screen Unlock. By replacing the physical sensor on the back of the phone to under the screen, the fingerprint reader takes up essential space inside, near the bottom of the phone.

It's also banking on its customers' use of Bluetooth headphones. After conducting a user survey, it found that 59 percent of respondents already used wireless headphones to listen to music and place calls. And for the first time since June 2016, sales of Bluetooth headphones overtook non-Bluetooth headphones in the US, according to analyst firm NPD.

"Consumers miss the 3.5mm jack when they're gone," said GlobalData research director Avi Greengart, "but Apple has shown that having them is not a primary purchase driver."

This has been one of the most difficult decisions for us to make. OnePlus CEO Pete Lau

By releasing its own Bluetooth earbuds earlier this year called Bullets Wireless, OnePlus set the stage for shifting 6T owners over to wireless headphones. So far, things are looking good -- within minutes, Bullets Wireless sold out in some regions.

Still, Lau knows that the move will be controversial, especially since plenty of people still use wired headphones. Wired headphones give you more options to shop from, they're cheaper, they don't require a charge and they don't run into connectivity issues. Last year, a Yahoo Finance survey reported that 73 percent of Android users said they wouldn't switch to an iPhone because of its lack of a headphone port. It also didn't help that Carl Pei conducted casual Twitter polls to show how much OnePlus listened to user feedback. Most of his respondents preferred to keep the headphone jack.

To those who are upset that the OnePlus 6T won't have a jack, Lau believes the tradeoffs are worth it. "After you experience the Screen Unlock you'll fall in love with it," he said. "[You'll] realize that it's the experience that you wanted."

And hello to the in-screen fingerprint sensor

Fingerprint-on-display sensors (or FOD) on phones are a rare find in the US. Right now, they're available on Vivo phones (the Vivo V11, X20 Plus UD, X21 and Nex) a couple of Oppo phones (Oppo R17 and R17 Pro), the Xiaomi Mi 8 Explorer Edition and the Porsche Design Huawei Mate RS.

But soon, users in the US and elsewhere will have the feature on the OnePlus 6T -- edging out both Apple and Samsung who are both rumored to include this technology in their future phones.

In addition to streamlining the OnePlus 6T's design, FOD eliminates the need to pick up the phone to unlock the screen.

"We unlock our phones multiple times a day, and Screen Unlock reduces the number of steps to complete the action," said a OnePlus engineer in a prior interview with CNET. "By adding this feature as an addition to other display unlocking options such as Face Unlock, users will have options to unlock the display in a way that is most efficient for them."

OnePlus

Despite being known as "in-screen fingerprint readers" the technology is actually embedded underneath displays. When you touch the designated area of the screen with your finger, a sensor array turns on the display to light your finger. Your fingerprint is then read by an optical image sensor and an AI processor. If the print matches, the screen unlocks.

Originally, last year's OnePlus 5T was supposed to have FOD. But it didn't work as fast or as efficiently as the company wanted, and the feature was delayed until the 6T. Along with OnePlus' implementation, Lau believes the phone industry will continue in this direction, similar to how onscreen notches caught on within a few years.

There are a few downsides to this fad though. Not only did OnePlus eliminate 6T's headphone jack because of the FOD, it also made the phone 0.45mm thicker. The feature also bumped up the overall cost of the phone. There's no official price out yet, but earlier reports tentatively put it at $550 -- or $21 more than the OnePlus 6.

"Screen Unlock technology is something very new and there's a definite cost required for that new technology," said Lau. "It's not cheap."

OnePlus' future: Wireless charging and water resistance

Since it launched the first OnePlus One in 2014, OnePlus was known for offering phones with premium specs at a wallet-friendly price. But the company is dealing with the dilemma of serving up similar features that iPhones and Galaxy S-devices offer, while keeping prices low. And compared to other brands, OnePlus has one of the highest increases in cost from model to model (the expected $21 price increase of the 6T is yet another addition to the steady climb of prices).

James Martin/CNET

Meanwhile, rival companies are incorporating cutting-edge technology into their phones at a neck breaking pace. Apple, Samsung and LG for instance, have phones with wireless charging.

But OnePlus' signature fast-charging technology, known as Dash Charging, is a fan-favorite feature. In order for OnePlus to release a phone with wireless charging, the device would have to charge as quickly as what users are accustomed to with Dash Charging. That means the phone would have to be thicker and it would conduct a lot of heat.

"We're working hard on this," said Lau. "When we get to the day that the wireless charging can get up to speed without the implication of heat that we expect, then I believe we can integrate the technology."

Many competitors, including Google, also certify their phones with an IP rating for water resistance.

But to Lau -- who says the OnePlus 6T is more water resistant than any of its predecessors and can survive an accidental drop in the sink or a splash during a rainstorm -- the cost to go through official IP certification just isn't worth it.

"The number of users that are taking their phone to go swimming are few and far between," said Lau. To have everyone else pay, say, $30 more, "for the sake of an IP rating" in order to accommodate the one user who goes off and swims with their phone is "unreasonable," according to Lau.

OnePlus 6T pricing

Incorporating these new features, which Lau isn't necessarily ruling out, all goes back to increasing prices. Though he insists that prices don't dictate the end product, and that giving people the latest and greatest in tech is the company's main priority, it's clear that OnePlus would lose its luster as the scrappy darling of the Android phone world if its prices were on par with its rivals.

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"As flagship phones from Apple, Samsung and Huawei are all topping the $1,000 price point," said Greengart, "OnePlus has a real opportunity to package leading edge technology at a lower price point."

For now, OnePlus is still mainly an internet-centric, direct-to-consumers online retailer, which helps keep costs low. In addition, a possible $550 price tag would still put it at around $100 to $450 cheaper than the iPhone XS, the Galaxy Note 9 and the Pixel 2.

Lau also doesn't appear too worried about any outcry over the OnePlus 6T's price either. He's more jazzed about users' reactions to the fingerprint scanner. And while he's no stranger to public events, his products launches are still cause for anxiety.

"The most difficult thing right now," said Lau, "is that the teams are expecting [me] to memorize English."

OnePlus confirms: The 6T will have an in-screen fingerprint sensor.

OnePlus 6T: Six features we're dying to see.