Here is a demonstration from a series of interactive-book android-apps that I will be putting up onto Google Play.
This book is The Wizard of Oz. Hopefully I will add this tomorrow.
The interactive-book removes the guess work from decoding words. The marks that are added to the text (once learnt) allow early readers to decode unfamiliar written words accurately.
There is a key to the sounds of all the marks. This marking scheme makes English regular. Thousands of, previously, exceptional words can now be read without guessing or permuting through all the possible combinations of letter sounds.
The Wizard of Oz is running on my low end Pixi 4 phone.
▶️ DTube
▶️ IPFS