Paula Hawkins's blockbuster debut, The Girl on the Train, led e-book sales for the first quarter of the year, from January to March. The book, released January 13, landed one spot above E.L. James's Fifty Shades of Grey, and Chris Kyle's memoir, American Sniper, adapted into a film of the same name, hit #3. Pulitzer Prize winner All the Light We Cannot See by Anthony Doerr came in at #4.

The sales figures and ranking come from PubTrack Digital, which is a publisher-aggregated e-book sales tool in which publishers supply confirmed e-book unit sales to Nielsen every month. Over 30 publishers supply figures and free e-books and books sold for less than 99 cents are excluded..

Top 10 Bestselling E-books, January to March, 2015

The Girl on the Train by Paula Hawkins (Riverhead)
Fifty Shades of Grey by E.L. James (Vintage)
American Sniper by Chris Kyle (William Morrow)
All the Light We Cannot See by Anthony Doerr (Scribner)
Fifty Shades Darker by E.L. James (Vintage)
Big Little Lies by Liane Moriarty (Putnam)
Gone Girl by Gillian Flynn (Crown)
Unbroken by Laura Hillenbrand (Random House)
Fifty Shades Freed by E.L. James (Vintage)
Private Vegas by James Patterson (Little, Brown)

Source: Nielsen PubTrack Digital