Huff and Puff
by Tish Rabe with illustrations by Gill Guile is a children's storybook in the My First I Can Read! series, free courtesy of publisher HarperCollins.
Currently free @ B&N
, where it will only work on a NOOKcolor/tablet or in the Nook Kids for iPad app (though you can still pick it up without having one, in case you want to anticipate a future acquisition). May possibly show up at iTunes as well, since some of these things have previously done so.
Puff is a caboose and Huff is an engine. These best friends try switching places in this rhythmic story for beginning readers. Features read-to-me audio, perfect for sharing.