It can cost as little as $50K for an MVP or even $500K for a complex product. Same as in the case of time estimations, we need to consider several important factors to assess the cost of developing your fitness app. Tell us about your project idea, and let’s discuss the further details, so we can collect all the necessary information (your requirements regarding the app’s type – web/mobile, features, technologies, etc.) and give you proper estimates.
Find more about costs here: https://neoteric.eu/blog/how-much-does-it-cost-to-create-a-fitness-app/