Hackers have infected one of China's most popular social media applications on Apple's App Store, Chinese Internet firm Tencent said, after dozens of programs were reportedly affected by a rare breach in the US giant's security.

WeChat, an instant messaging application developed by Tencent, has hundreds of millions of users in China and around the world.

A powerful earthquake strikes off the Pacific coast of Mexico. Within seconds, radio transmissions, megaphones and smartphone apps blare warnings to the capital's 20 million people before the ground shakes.

After the loud "seismic alert!" alarm, Mexico City residents have as much as a minute to flee their homes, offices and schools before buildings start to sway.

Facebook unveiled a new tool Thursday aimed at helping journalists using the social network track breaking and trending news, in a challenge to Twitter.

The service called Signal, which is available for both Facebook and the Facebook-owned Instagram platform, is designed for journalists who are using social media as part of their reporting efforts.

Amazon unveiled a major home electronics push Thursday, led by a $50 tablet computer and other devices aimed at budget-conscious, gadget-hungry consumers.

The low-cost, seven-inch (18-centimeter) Fire tablet is part of an upgraded line being launched by the online retail giant, along with updated Fire TV streaming media devices and a new game controller box.

Apple is delaying a big software update for the Apple Watch because it found a bug that is taking longer than expected to fix.

Apple Inc. said in a statement that it will not release watchOS 2, the new operating system for the Watch, on Wednesday as planned. It did not say when it will launch, only that it will happen "shortly."

Apple has given its latest iPhones an environmental upgrade to go along with a better camera and a few new features.

The iPhone 6s and 6s Plus have reduced their carbon emissions by 14 to 16 percent from last year's models, according to Apple measurements that quantify how much pollution is caused during the production, distribution, consumer usage and recycling of the devices.

Smartphone users now have more than 165,000 apps available to help them stay healthy or monitor a medical condition, but just three dozen account for nearly half of all downloads, according to a new report.

Most apps focus on fitness or wellness by helping the user do things like count calories or track steps walked. Doctors and other care providers also are taking a growing interest in using apps to help patients, but concerns about a lack of research and data protection are limiting wider use of the technology, the IMS Institute for Healthcare Informatics said.

More than 100 million users are on Pinterest, the online bulletin board-style service which allows people to "pin" images based on their interests, the California company said Wednesday.

Co-founder Evan Sharp told Agence France Presse that most of the users "are not just visiting Pinterest once a month, but they're actually discovering something so interesting that they're saving it or are clicking through to the website."

The digital era is cutting into income for book authors, making it more difficult to live off writing alone, a survey by the Authors Guild said Tuesday.

The survey said income for full-time U.S. authors in 2015 fell 30 percent from 2009 to $17,500, and part-time authors saw a 38 percent drop in income to $4,500.

Facebook, pressed for years by users to add a "dislike" button, announced Tuesday it was working on the feature and will be testing it soon.

"We've finally heard you," CEO and founder Mark Zuckerberg told a public town hall meeting in Facebook's hometown of Menlo Park, California.