【Dead Again】

The Dead AgainNASA app has always been a solid scientific resource for armchair astronauts, but some recent updates have taken it from educational to sensational. This is in part due to a new augmented reality tool, stunning 360-degree videos, and an awesome use of the widgets functionality in iOS 14.

If it's been a while since you took a look at NASA's app, or if you haven't yet had the time to take a look, then have a read through our four stellar reasons below that explain why it's high time you check it out now, no rocket or rover required.

1. A galactic gallery

The NASA app contains as many as 19,000 official images that you can browse, rate, and favorite. What we love about the NASA image database is that as well as share the images, you're completely free to use them as your smartphone or tablet's wallpaper or lock screen image, which can look out of this world.

To save or share an image, simply tap on the screen and look for the action options. On iOS, this is a box with an arrow icon that will appear at the top right of your screen.

Credit: nasa app

In addition, for iPhone and iPad users, thanks to the new widget creation functionality in iOS 14, which adds mini shortcut applications to your homepage, you can enjoy a fresh NASA image update every day without even opening the NASA app.

Developer Mark Hambly has created a NASA-powered astrophotography widget that showcases NASA's "Astronomy Picture of the Day" project. It's 100% free, with no ads.

Credit: nasa app

You can download the widget app, which's been developed especially for iPad but is also available for iPhone, here. This is obviously not the full NASA app, but a third-party offering for iOS which gives you a handy Astronomy Picture of the Day update.

2. ISSential viewings and notifications

If you're fascinated by the International Space Station then this app is going to be a radical resource for you. Through the app, you can see the ISS's view of the Earth andset up ISS pass alerts to give you a heads up when it passes over your location.

To enjoy the view from the International Space Station, which as you can imagine at times is absolutely amazing, go to the "TV and Audio" section of the app from the app's homepage.

Now, at the bottom of the screen, you'll see the "ISS Views" tab. Click this and you'll see the live stream of Earth from the ISS's High Definition Earth Viewing experiment.

Chill view of Earth from the ISS Credit: nasa app

Alternatively, if you want to view the International Space Station from the ground looking up, you can set up alerts to get notifications when the ISS is due to pass your location. To set these up you first need to allow the NASA app to give notifications.

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To set up your sighting notifications go to the app's home screen and tap on the three lines menu icon at the top right of your screen. On the next page, toggle "Configure Notifications for ISS Sightings" to on.

Credit: nasa app

You'll now see the option to get notifications five, 10, or 15 minutes before the ISS is due to pass your location.

3. Star-studded next-gen video

The NASA app has a really robust video collection that includes some totally fascinating next-generation visual content. These include immersive, 360-degree interactive videos and eye-popping, high-definition, 4k content.

To enjoy these free offerings, head to the "Videos" section of the app from the homepage. If you look to the bottom of the screen, you will see the choice to tab between NASA's standard video content, 4K content, and 360-degree clips.

Credit: nasa app

Simply tap on each tab to see what's available to view.

The 360-degree videos work brilliantly on mobile devices, giving you the opportunity to pan around video footage of NASA missions, feel like you're in the room during live Mission Control events, see 360-degree visualizations, and check out the view from NASA's Curiosity Mars Rover.

Credit: nasa app

You won't get the full benefit of the 4K high-definition videos on the average smartphone or tablet's screen, but they still look impressive. This content really shines for those with 4K capable TVs who can enjoy the absolutely jaw-dropping 4K content via the Apple TV, Amazon Fire TV, and Roku apps.

4. See NASA gear in your own home

Credit: nasa app

The NASA app saw a recent update that brought some brilliant augmented reality content. You can access this astonishingly great functionality if you have an up-to-date smartphone or tablet.

Simply head to the "Featured" section from the NASA app's home screen. Then, if you have a compatible device that can handle AR content you'll see a sub-section for "Augmented Reality 3D Models." Just tap on this and from the menu that appears, select which NASA machinery you want to see brought to life and point your device at a flat surface.

Want a Pegasus rocket in your living room? Done. Credit: nasa app

This feature borrows tech from a standalone NASA augmented reality Android app called Spacecraft AR, originally produced by NASA's Jet Propulsion Laboratory in Pasadena, California. It uses AR technology to put virtual 3D models of NASA's robotic space explorers into any environment with a flat surface.

Or maybe a rover? Credit: nasa app

3D models you can bring to life include NASA's Curiosity Mars rover, and the Juno, Cassini, and Voyager spacecraft. You can also see the giant 70-meter NASA Deep Space Network dish.

Where to get the NASA app on all available platforms

Credit: nasa app

The NASA app is a cross-platform offering although, obviously, full functionality won't be the same across all devices.

The NASA app and related content can be downloaded, for free, in the following places:

• Here for iOS

• Here for Android

• Here for Amazon

• Apple TV users can go to the App Store on their Apple TV device to install

• Amazon Fire TV users can go to the Amazon Appstore on their Fire TV device to install

• Roku users can visit the Roku Channel Store on their device and add the NASA channel

Happy space exploring, armchair astronauts!