Apple has released updates for many of its products to fix a major bug in FaceTime. The update fixes an issue that stopped newer devices from calling those with older software, leaving iPhones and Macs unable to communicate with each other. The problems came as many people around the world rely on FaceTime to communicate with loved ones and colleagues through coronavirus lockdowns. All of the new software updates are available now. They can be installed in the usual way, through the Settings app on iPhone and iPad, the App Store on Mac or in the devoted Watch app.

Zoom has released a major new update as it continues to grapple with its security problems. The video chat company also announced that it has recruited former Facebook executive Alex Stamos to serve as an advisor, in an attempt to fix its problems with privacy. Mr Stamos served as Facebook's chief security officer during some of its most controversial years, including the 2016 election. The new update to the Zoom client, numbered 4.6.10, "focuses on critical security and privacy updates", according to Zoom.

The development of 4G's successor began before the fourth-generation wireless network had even rolled out. In 2008, less than a year after Steve Jobs unveiled the first ever iPhone, Nasa started work on 5G in the hope that the futuristic technology would one day facilitate "a new economy in space". It would take another year before 4G became commercially available, which together with the iPhone led the way for a decade of new apps, devices and innovation. But while 4G was an era-defining technology that boosted the speed and utility of already existing products and platforms, the fifth generation feels to some like a solution in search of a problem. While Nasa's research foreshadowed the development of a space-based internet built on 5G networks, there have yet to be any revolutionary applications that people can actually use.

New emoji have been delayed by the ongoing coronavirus pandemic. There will be no new characters next year as the volunteers who help create them are struggling to deal with the health situation across the world, according to the Unicode Consortium, which organises new emoji releases. The new emoji that were announced earlier this year – which include transgender representation and extinct animals – are still expected to make their way to iPhone, Android and other platforms through the course of 2020. But the new updates that would have been planned for 2021 have been pushed back to the following year. Version 14 of Unicode's standards, which would have included the new characters, has been delayed by six months, it said.

Facebook has added a "quiet mode" to its app, in an attempt to make it less stressful. The company said it had rolled out the feature as part of a wider response to the coronavirus pandemic, to improve the wellbeing of its users. The quiet mode allows a user to turn off notifications from the mobile app, and can be turned on manually or at certain times of the day. Facebook said the new feature should make it easier to limit the time spent online, as people are at home more than usual. "As we all adjust to new routines and staying home, setting boundaries for how you spend your time online can be helpful," the company wrote in an update to its coronavirus hub, where it has collated other responses including attempts to address widespread misinformation on the site.

Zoom will let its paid users decide where their data is going after its latest privacy scandal. The changes come after criticism over the fact that users' data was being sent through servers in Chinese data centres, potentially allowing conversations and video chats to be intercepted by the Chinese government as they were sent. Zoom said its centres in the country have "always been" geofenced, meaning that data generated outside of China would not move through the country. But chief executive Eric Yuan admitted that in the rush to meet demand during the coronavirus lockdown some best practices were not implemented and some meeting data may have been routed through China. Mr Yuan said this issue had since been corrected.

Apple has released data from its Maps app to track whether people are complying with coronavirus lockdowns. The data shows whether its users are still requesting directions from their iPhones, and so can be used to see how much people are travelling compared to before the lockdowns came into effect. It shows a dramatic reduction in the number of people using driving, walking and transport directions to get around, suggesting that stay-in-place orders and other rules to stop the spread of coronavirus are working. In the San Francisco Bay area, for instance, requests for driving directions are down 70 per cent, and people looking for transit directions have dropped 84 per cent. In New York, transit requests were down 89 per cent.

A security vulnerability with the popular app TikTok could allow hackers to post fake videos to people's accounts, researchers have warned. App developers Tommy Mysk and Talal Haj Bakry were able to manipulate popular TikTok accounts to make it appear as though they were endorsing dangerous conspiracy theories and hoaxes surrounding the coronavirus pandemic. "Washing hands too often causes skin cancer," one fake post on the official UN Migration account states. A blog post detailing the threat urged TikTok to switch from the HTTP protocol to the more secure HTTPS in order to prevent future attacks. It explained that the use of HTTP to transfer sensitive data meant they were able to intercept TikTok traffic and trick the app into showing the fake videos as if they were posted by the users.

TikTok users under the age of 16 will soon no longer be able to send or receive direct messages through the hugely popular video-sharing app. From 30 April, new online safety measures introduced by the Chinese-owned app will stop children from using the Direct Messaging feature to contact other users. TikTok's head of safety Cormac Keenan explained that the ban is aimed at "going one step further" with its existing restrictions, which already prevent users from receiving unsolicited messages from people that are not friends with them in the app. "As part of our commitment to improve safety on TikTok, we are introducing new restrictions on who can use our Direct Messaging feature," he said. "Direct Messaging is an amazing tool that enables people to make new friends and connections no matter where they are in the world. But despite its potential for good, we understand the potential for misuse."

Collin Kaufman at the University of Illinois at Urbana-Champaign and his colleagues built biological robots using 3D-printed muscles made of lab-grown mouse cells. But on their own, the muscles can't do much – what is needed is some way to control them.