Yes, Cold Correct 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.
Cold Correct is free.
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App calculations appear to be fine. My only complaint is the user can only calculate one altitude at a time. Most approaches have multiple altitudes that must be corrected. (IAF, FAF, Step Downs, DA / MDA, Missed approach alt, etc.) A really nice feature would be to have several altitude entries to do all the calculations at once.
