Don't Let the Pigeon Run this App! was the first app featuring Willems's earnest and exuberant Pigeon. In that production, viewers had both storytelling input and an opportunity to draw the Pigeon, guided by step-by-step instructions from the author. Mo...on the Go! offers more games, more Willems characters, and cameo appearances by the author. The Pigeon is back, and this time he’s joined by several other beloved Mo Willems characters in Pigeon Presents: Mo…on the Go! (Disney Publishing Worldwide Applications; $3.99 iOS; $2.99 Nook; PreS-Gr 1), an impressive app with a number of entertaining game options. Child and adult narrators instruct users on how to operate the activities as upbeat piano music sets the playful tone. In the “Pigeon’s Dream Drive” children steer a bus driven by the Pigeon through a maze of streets. The object? To pick up ducklings without being caught by a mad cow. Honking horns, barking dogs, and quacking ducklings add to the fun. “Dance-o-Rama,” featuring Gerald and Piggie, asks users to choose three dances for each character to perform on a stage to the tune of disco music. Leonardo the Terrible Monster hosts the “Monster Maker,” which requires swiping the screen to choose from an array of body parts to build a creature. Children can also create Knuffle Bunny-inspired pictures using the iPad camera. The sepia photos with stickers of characters from the book can then be saved or shared via email. Willems makes cameo appearances in both the “Monster Maker” and “Dance-o- Rama” (where he shows off some fancy footwork), and he's the host of the “Mo’s Squillems,” a drawing activity designed for one or two players. In that game, children create pictures based on a squiggly line provided on the page. Each visit brings a new line, offering endless possibilities. Mo…on the Go! is more than just pure entertainment; it encourages imaginative play and problem solving. The variety of options, the focus on creativity, and Willems’s quirky humor will have young fans (and adults) returning again and again.—Cathy Potter, Falmouth Elementary School, Falmouth, ME