App reviews: Star Chart, Duet

On summer nights, there's nothing quite like gazing at the sky and taking in the stars. But what exactly is up there?

With this app, you can point your phone at the sky and bring up illustrated versions of the constellations around you, which you can tap for basic information.

You can also choose to see how things look in other places. There are also in-app purchases you can make to enhance its function and more deeply explore the planets.

There are a lot of star map apps out there that give you more, or perhaps more comprehensive, options for heavenly exploration by aid of your smartphone. But Star Chart is free to download and more than covers the basics. Free, for iOS and Android devices.

Duet

The aim of this game is pretty clear: Just don't hit anything.

Players spin toward the end by navigating a maze with a circle that has two colored dots on it. Tapping the screen in either lower corner will rotate the disc to the right or left to help you move the dots past obstacles.

It's harder than it sounds. And the game doesn't let you forget your failures. Smacking into the wall leaves a colored mark that stays even after you've been rewound to the start of the level. That can be frustrating or motivating, depending on your personality.

Still, the game's soothing soundtrack can keep you calm as you repeatedly hit the same wall.

There's plenty of replay value here, and there's even an endless mode if you get really good at dodging. The app is $2.99 for iOS devices and free for Android devices.