It's no secret that along with dinosaurs and construction sites, trains make the list of preschool and early elementary students' favorite topics. Here's an app that combines exploration with story and creation activities. The app is the first in the DADA Collection, which offers "edutainment activities and experiences designed around one common thread." Deb Whitbeck reviews it below. Know any train enthusiasts? If so, introduce them to Dada Trains (DADA Company, iOS, $2.99; PreS-Gr 3), an app that offers multiple levels of exploration. Currently featuring five activities, the youngest users will simply drive the trains through various terrains and weather conditions in "Simulator," with options to stop and go, and control the speed, or change the look of the control panel. The "Look Inside" mode allows a peek into the workings of a steam train where users can interact by adding coal to the boiler and watch as the engine picks up speed. "Playground" features the train going in and out of tunnels, over bridges and past roads where users tap/swipe to open gates and discover hidden characters. Children with artistic inclinations will enjoy the "Magic Canvas," which includes background options of screen shots. More engaging for future engineers is "Train Factory" where kids design their train using a menu of fill-colors, then travel through challenges such as broken tracks until reaching their destination. Luckily, there’s a reset button for users who cannot solve a problem and would like to begin again. Cheery graphics  in a number of styles and entertaining sound effects heighten the experience. No instructions are given, which in this app, encourages exploration. A recording option is available. The range and variety of activities and promise of future updates with more content will have children visiting this production time and again. The app is available in Spanish, English, and a number of other languages.—Deb Whitbeck, formerly of West Ottawa Public Schools, Holland, MI  

Tap the stoker to increase the speed of the engine. Interior screen from DADA Trains (DADA Company)