Mr Thorne's Spellbook is an educational and entertaining spelling app for kids available on the iPhone. Developed by Queue Press Limited, this app offers 101 spelling tests based on teaching letters and sounds, starting with simple words and progressing to more complex ones. The app focuses on digraphs, trigraphs, and challenging spellings like the 'silent u' and the /er/ sound in 'earth.'

In the game, the player is required to spell the word correctly after listening to it and sometimes using capital letters. The game also features a score system, where the player must score 10 out of 10 to unlock the safe and obtain the treasure. The game structure is designed to match a child's ability, ensuring that the words in each game are in sync with their level.

Overall, Mr Thorne's Spellbook is an engaging and challenging spelling app that helps kids improve their spelling skills in a fun way. The app is easy to use and the treasure hunt feature motivates kids to keep playing and learning.