Upon opening, Planet Lettra (Studio Goojaji, 2015; iOS only) offers the option of taking a young user–friendly tour. I recommend starting there — the app looks simple, but there are a number of quirks that would’ve taken me a while to figure out without the help. As the tour explains (in rhyme), Planet Lettra has bubbles floating above it, containing letters, blends, and words. On the surface of the planet, creatures are hanging out; you can spin the planet to choose which creatures you want to play with. The creatures behave differently and serve various functions, but many eat letters, blends, and/or words — and in some cases, change their appearance when they’re fed.

Drag bubbles toward each other to create new blends and words. Individual letters appear in white bubbles, blends in yellow bubbles, nonsense words in blue bubbles, and words the app recognizes in orange ones. You can select your language in Settings, and one bubble lets you switch from one country’s dialect of that language to another (U.S. to Australian, British, or Irish English, for example). In the settings menu, you can also customize the text that appears in some of the bubbles; words and blends you’ve saved will appear in pink bubbles.



Once you get a sense of which creatures and features do what, there’s a lot you can control. Tilt the rings of the planet in the upper right corner to control how permeable the bubbles are, and thus how easy it is to combine them. Tap the green moon in the upper left corner to split up that blend you just made by mistake. There are creatures you can tap to exchange all your bubbles and start over, and little Saturn-like planets that will convert one letter to another — the left one will change it to the next letter in the alphabet, and the right one will move it through the alphabet backwards. And one creature, when tapped, will show you the belly of the planet itself, where you’ll find any (real) words you’ve fed to the creatures. You can sort the words in a few ways (alphabetically, by length, etc.), hear them read aloud at different speeds, or dispose of them. Appropriately spacey-sounding music and creature sound effects enhance the out-of-this-world setting.

This app takes some figuring out, but that’s part of the fun. And once you do, it’s a great way to experiment with building sounds and words.

Available for iPhone, iPad, and iPod touch (requires iOS 8.1 or later); $1.99. Recommended for primary users.