Sight reading isnt teaching phonics

Wondering if this app is good for a 3rd grader.
I moved my son to private school where I learned he was struggling to read. Had him tested and found out he was never taught phonics in school!!!
I want to purchase full app but need to know if its too babyish or would it help?

Not a fan of public schools about Hooked on Phonics Learning, v5.0.10