By Tony Hoffman

NASA has released many iPhone apps, most with a specific focus: for example, NASA Television is a viewer for the space agency's own TV channel, ISSLive gives the latest on the International Space Station (ISS), and NASA Space Weather explores solar flares, geomagnetic storms, and the like. NASA App (for iPhone) is the space agency's flagship app, and in that role, it aggregates a wide range of NASA content, including much that isn't found in the other apps. This frequently updated app has well-written news stories, dazzling videos and images, a portal to streamed NASA tv and radio, information on NASA missions present and future, how to visit the various NASA centers, and much more. There's something for everyone, from children and students to seasoned space geeks, in NASA App, and it's an easy pick for Editors' Choice.

Into the Grid Opening the app in portrait mode reveals a grid of 9 squares. The sections are titled Missions; Images; Videos; Tweets; TV & Radio; News & Features; Centers; Features; and Programs. Missions gives information on active and upcoming NASA missions. The first two items are Launch Schedule and Sighting Opportunities. Launch Schedule gives information about upcoming launches by NASA (and SpaceX; the first mission mentioned is that company's Falcon9 ongoing resupply flight to the ISS) and its ISS partners. Sighting Opportunities tells you how to view the brightest satellites/spacecraft (mainly the ISS) from your location.

The Missions are then listed in alphabetical order; tapping one takes you to a page with information about it. They include well-known missions such as the Hubble Space Telescope and more obscure ones like Calipso (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation), a joint U.S./French meteorological mission that studies clouds and aerosols.

Dazzling Images and Video Images offers more than 9,000 beautiful images on a huge range of subjects, from the Hubble Extreme Deep Field view of distant galaxies to the Space Shuttle Endeavour being transported through the streets of Los Angeles. Tapping on an image, and then tapping on the "I" button in the screen's lower left calls up information on the photo. New photos are frequently added.

In the Videos section are nearly 9,000 well-produced and informative video clips, and new ones are frequently added. You can see cool videos showing the latest on the Curiosity Mars mission or ISS, clips of solar flares and other phenomena, and much more. You can mark a video as a Favorite, email the video, or post it to Twitter or Facebook.

The rather cumbersome Tweets section brings up recent tweets from a range of NASAaccounts: @NASA; @NASA_ICE; @NewHorizons2015; NASAGoddard; and many more. You can email the tweets, post them to Facebook, or retweet them. However, when you retweet name of the NASA twitter account disappears, so you have to enter it yourself after the @. Likewise, you can reply to the tweet, but you have to click on a twitter handle within a tweet, click on the Write icon, and compose a tweet from scratch. (Once again, it doesn't automatically pick up the Twitter handle of the NASA account.) It can be used as a normal Twitter client, but it's awkward as such.

TV and Radio lets you access Third Rock, NASA's rock music Internet radio station, or NASA TV, either the primary stream or an alternate, and provides video-out support.

Your Source for Space News To help you keep up on the latest space news, News and Features is a growing repository of more than 3,000 well-written and informative stories, under headings such as "Top Stories" "History and People" "NASA in Your Life" "Station and Shuttle" "Breaking News" "Solar System" and more. You can search News and Features for articles on specific subjects, and individual stories for keywords. You can print stories (via AirPrint, if you have a compatible printer on your Wi-Fi network), post them to Facebook or Twitter, or email them.

Visiting NASA Want to visit the Kennedy Space Center, or a similar NASA facility? Centers lets you plan a trip to a NASA center. It shows a map of the U.S., with each NASA center marked by a red pin, and your location marked in blue. Tapping a pin brings up information on visiting that center, including hours of operation, ticket info, and links to other useful information.

The rest is here:

NASA App (for iPhone)