Yes, Functionator is completely free and it doesn't have any in-app purchases or subscriptions.
Not enough reviews to make a reliable assessment. The app needs more user feedback.
Functionator is free.
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I use this with my first graders. The problem I am having is What's My Rule? I can't choose beginner or novice so everything that comes up is division or multiplication. I want my kids to use addition and subtraction. Also 0 should be an option on the wheel.
