There are 3 books in the Invisible Inkling series.
The Invisible Inkling series does not have a new book coming out soon. The latest book, The Whoopie Pie War (Book 3), was published in July 2013.
The first book in the Invisible Inkling series, Invisible Inkling, was published in May 2011.
The Invisible Inkling series primarily falls into the General Fiction genre. This chapter book series was written for ages 7-10, but some older readers may still like to read these books.