Our editorial rating – an impression of the whole book overall. We also consider how the app compares to other apps currently available. Note: It is not a sum of the other ratings.

The average rating from users signed into the Digital-Storytime.com site (who checked the 'own it' box).

We consider both technical & visual appeal of the animated elements. We focus on quality rather than quantity, although very little animation will rate slightly lower on this scale (to allow proper sorting).

Overall quality of audio elements. We consider whether the music & sound effects are easy to listen to and well-matched to the story. Narration, when present, should be clear & well-articulated.

We consider all the interactive elements of a book app. We look for interactivity that is well-matched to the story & engaging but mark down for interactivity that interfere with reading comprehension.

Overall value the app can offer, either as a book app that can occupy the reader for hours or a story that will be returned to for many re-reads. We do not take price into consideration, since it often changes.

We consider length (under 10 minutes is ideal), enhancements & extras (ideally not too overstimulating), as well as story content that is appropriate for children at night-time.

Overall educational value. We consider enhancements, added content (like reading comprehension questions or other suggested activities) and any unique educational value that makes the app stand out.

We consider the story, art, concept, design & execution of the app. Apps based on folktales & previously published titles will score lower unless they have a unique presentation.

We consider anything in the app that goes beyond the story, like games, puzzles, coloring pages, etc. High ratings in this category mean the extras are well made, engaging and have high replay value.