RedShift is a $12 universal planetarium app. Like the awesome Pocket Universe, this app from USM aims to bring the entirety of the nighttime sky onto your iOS device. It’s amazing.

With your permission, Redshift uses your current location to show you precisely which stars, constellations, and planets you should be able to see. If you enable the Follow Sky option, RedShift will update what you should expect to see as you point your iPad or iPhone at different spots in the sky while you pan around. If you can generally just pick out one of the Dippers, Red Shift will open your eyes to many more constellations.

An observatory option lets you jump from your own location’s view of the sky to any celestial object you’d like to see—the moon, a planet, or a specific star. You can zoom in to impressive levels of depth, too.

One especially fun feature is 3D Flight mode. Instead of just jumping directly to, say, Jupiter, you can have RedShift animate the zippy journey past stars and planets. (Fortunately, this space travel does not occur in real time.) There’s even a Grand Tour option, in which RedShift takes you from the Moon to Mars, Saturday, and beyond. It’s truly excellent.

Once you’ve navigated to a a specific space object, you can tap into Rotation Mode. That lets you spin the planet around in all directions, which can also adjust your view of the rest of the galaxy from different vantage points around the planet, moon, or star. Whenever you’re locked onto a specific object, you can also tap on an i button to see basic information about it—where it is, how many moons it has if applicable, its size, and so on. There’s also a Wikipedia button that you can tap, which loads the appropriate article without exiting RedShift.

The app is packed with options. Night Vision mode casts the whole app in a red-toned hue, making it easier to use outside in the dark without blasting out your retinas. You can control whether constellation images should be displayed, or just the traced outline of the stars, or nothing at all. You can adjust how bright or dim each should be. You can control whether labels for each heavenly body should appear in English, Latin, or Brief Latin. You can control how many heavenly objects and labels appear on the screen at any given time, toggle sound effects, and even trigger an option to see the (decidedly less interesting) daytime sky.

A search box at the upper-right of the screen lets you search for whatever you’d like to see. A button at the top left works as a perfect reset switch; if you get lost in space, it brings you right back to your view from home instead. And if you want to see the sky for a different date or time, you can adjust that at the bottom of the screen.

iOS device owners enjoy an embarrassment of riches when it comes to astronomy apps. Vito Technology, for example, offers Star Walk, which is very well-regarded in both iPhone and iPad formats. Redshift and the aforementioned Pocket Universe are also superb, and I found each easy to master after a short learning curve. If you can only buy one, you should probably judge on looks alone: which one sports the slicker interface? Were I myself forced to choose, I’d give Pocket Universe’s visuals a slight edge, but would feel as sad about losing Redshift as I did when Pluto lost its planetary status.

RedShift is as impressive as it is immersive. The app is packed with data, and it makes a great stargazing companion if you, like me, need a little help understanding what you’re seeing in the sky.

[Lex Friedman is a frequent contributor to Macworld.com]