My two primary age children are huge fans of Doodle Maths, especially the one who can't stand to be taught anything (SEN but bright and good at maths).
My young relative failed their National 5 but passed their National 4 and now needs to resit National 5. I am aware that Doodle Maths goes up to KS3 and if they turn out to be really shaky on that part of secondary Maths I'm really happy to give them my discount code for Doodle Maths but I suspect it's too easy for her, unless other people know better?
But given that the relative is quite unconfident and has in the past been resistant to being "taught" I'm thinking of recommending an app - ideally one that has really good explanations, and that sets the appropriate level for the child, because I've looked at other apps that don't do this. Also that isn't glitchy (My Maths I'm looking at you on all grounds).