HANNA & HENRI

Backyard robot-building is the order of the day in an app that will appeal most to budding tinkerers.

Two young friends, Hanna and Henri, meet up to visit Hanna's aunt, a goggles- and apron-clad inventor. Hanna and Henri work together to create their own robot (with some help from readers to sort parts and choose the creation's look in one of several challenges). How much readers enjoy this will depend on their tolerance for extraneous characters and locations that have nothing to do with the main story. There are also two minor annoyances: The text is too tiny to be read without manually adjusting its size (an option in an easy-to-access sliding menu), and load times between screens feel slow in this otherwise very responsive app. On the other hand, the app has pleasingly detail-heavy art that appears hand-drawn, and the depictions of women and girls in the story as inventors and robot builders are refreshing. But perhaps the biggest selling point is that the central robot project can be built in lots of different ways, making the story one that invites repeated read-throughs. The animation is fluid, and the resulting robots never fail to be worth the trouble. There are even pages of bios for all the story characters.

A mostly solid piece of garage building with winning characters and very cool robots.