Artificial intelligence is helping computers drive cars, recognize faces in a crowd, and hold life-like conversations. General Electric engineers now say they've used the data-intensive technology to develop tools that could cut the industrial giant's design process for jet engines and power turbines in at least half, speeding up its next generation of products. Today, it might take two days for engineers to run a computational analysis of the fluid dynamics of a single design for a turbine blade or an engine component. Scientists at General Electric's research center in Niskayuna, New York, say they've leveraged machine learning to train a surrogate model so that it can evaluate a million different variations of a design in just 15 minutes. "This is, we think, a huge breakthrough," says Robert Zacharias, technology director of thermosciences at GE Research.

Apple will finally fix your iPhone, even if it has someone else's battery inside. Until now, iPhones with replacement battery that were installed by someone other than Apple employees have been excluded from being fixed. They were ineligible to be looked at by the Genius Bar, for instance, meaning that getting a battery replacement could mean passing up the chance for any other service work. That was the case even if the problem was with another component and not the battery, meaning that the entire phone would be banned from repairs just for having a third-party battery. We'll tell you what's true.

When I reviewed First Alert's Onelink Safe & Sound smoke alarm in mid-2018, I found it to be a powerful entry in the smart smoke detector market. Its inclusion of Bluetooth and an Amazon Echo-compatible smart speaker set it apart from every smoke and carbon-monoxide detector on the market. But its $199 price tag also made it far and away the most expensive device of its type on the market--and that price hasn't budged since its release. Enter the Onelink Smoke Carbon Monoxide Alarm, which lowers the cost of the original product by stripping out its most compelling features: The smart speaker and Bluetooth. Like other products in this category, the Onelink Smoke Carbon Monoxide Alarm is designed to extend the capabilities of a smoke detector by linking it with your smartphone. It still functions by firing off a (rather loud) local siren whenever smoke or CO are detected, but it also (supposedly) sends push alerts to your mobile device, a feature that is most helpful for times when you aren't at home but still want the peace of mind that it's not on fire.

This is not a story about how the polar vortex is bad--bad for the human body, bad for public transportation, bad for virtually everything in its path. This is a story about how one being among us is actually taking advantage of the historic cold snap: Cassie the bipedal robot. While humans suffer through the chill, this trunkless pair of ostrich-like legs is braving the frozen grounds of the University of Michigan, for the good of science. "When we saw the announcement for the polar vortex, we started making plans to see how long we could operate in that kind of weather," says roboticist Jessy Grizzle. "We were going to tie a scarf on her just so it looked cute, but we decided people would think that was keeping her warm and affecting the experiment, so we didn't." Scarves aside, this is vital research for a future in which robots tackle not just polar vortices but any number of other brutal environments.

Amazon is selling a robotic toilet cleaner for $499.99 (£400) that will keep the lavatory squeaky clean for you. The droid is called Giddel and is designed to scrub the rim and bowl of a toilet so customers don't have to complete the arduous chore. It weighs more than six pounds (3kg) and is powered by a rechargeable lithium-ion battery. The hefty price tag includes the robot, cleaning accessories and an elongated toilet seat to allow the robot to clip on. Amazon is selling a robotic toilet cleaner called Giddel (pictured) for $499.99 (£400) that will keep the lavatory squeaky clean The droid is designed to scrub the rim and bowl of a toilet so customers don't have to complete the arduous chore It weighs 1.5 pounds (3kg) and is powered by a rechargeable lithium-ion battery.

An amphibious supercar design that would allow its mega rich owners to look stylish and beat city traffic by travelling through water at high speed has been unveiled. According to its creators, the electric powered Amphi-X would reach speeds of more than 260 mph (418 km/h) on land and an average speed of over 90 mph (145 km/h) in water, the same as a modern speed boat. The car has been designed for the world's super rich to avoid congested roads of big cities, but comes with a hefty £2.5 million price tag. An amphibious supercar design that would allow its mega rich owners to look stylish and beat city traffic by travelling through water at high speed has been unveiled. The car has been designed for the world's super rich to avoid congested roads of big cities, but comes with a hefty £2.5 million price tag.

Vava has unveiled a new pet camera that will let you follow your dog or cat around the house when you're not home. The device, said to be the first mobile pet cam in the world, made its debut at CES in Las Vegas this week. Vava's Pet Cam is equipped with two-way audio so you can hear and speak to your pet remotely, and collision detection will let it roam the house without bumping into anything or falling down the stairs. Vava has unveiled a new pet camera that will let you follow your dog or cat around the house when you're not home. The Vava Pet Cam connects with an app that lets you interact with your pets from afar.

LAS VEGAS--Get ready to peek at a new Ring. For homes and apartments that don't have doorbells, the folks behind the Ring video doorbell have a new offering, the Ring Door View Cam. The company describes it as "a wire-free video doorbell that transforms a door viewer into a smart security device." Jamie Siminoff, the founder of Ring, says the peep hole cam has been one of the top requests from customers. "There's a small subset of people who don't have room for a door bell," he says.

The reduced-price replacements last until the end of the year, at which point the cost will dramatically increase. For the moment, a new battery costs only £25 – but once the new year arrives, that will rocket up to as much as £65. Old batteries can cause significant problems for their owners as iPhones age. With use, the power begins to drop – something that can lead to phones lasting for much less time, and to Apple having to slow down phones to ensure that they don't crash because they're not getting enough power. It was the revelation that Apple was doing that – throttling performance on older phones, in line with more spectacular rumours that swirled before it was admitted – that led to the cheap repairs in the first place.

This post was done in partnership with Wirecutter. When readers choose to buy Wirecutter's independently chosen editorial picks, Wirecutter and Engadget may earn affiliate commissions. Read Wirecutter's continuously updated list of Black Friday deals here. This drops the Series 3 38mm, and the 42mm ($230) to the best prices we've seen to date, almost $60 below recent sales. The Apple Watch Series 3 is the budget pick in our guide to Apple Watches. Nick Guy and Dan Frakes write, "It was introduced in 2017, but it offers most of the features and experience of the Series 4 at a significantly lower price. The Series 3 models have smaller screens--the biggest obvious difference--aren't as speedy, don't do automatic workout detection, and won't support the Series 4's ECG feature or fall detection. Even so, the Series 3 is still fast, designed with the same GPS features and swim-friendly waterproofing, and equipped with a bright screen that's easy to see outside."