I have read in different pages like reddit or X that freemium models do not tend to convert well. I thought quite a lot about this when I was building WorkoutOS and started setting up the Stripe product. After some time, I decided to go for a freemium model anyway. While it might be true that this kind of business model struggles to get good conversions, I also thought about the joy of building this app and the benefits it can bring to people.
Throughout this journey I have enjoyed learning more about programming, creating a platform that generates strong analytics and powerful visuals that I enjoy daily. This, by itself, is a great reward, even without paying customers.
Some weeks later, after have been using it regularly, I have seen that it has helped me to stay motivated and exercise better where I was not feeling it (the workout streak is an awesome metric for this). And I thought "Wow, this could help many to reengage with working out and getting healthier". This reinforced the idea that freemium might be the right choice, even if it does not bring direct payments.
Building apps and having startups is not just about getting paid, it is also about helping others. If I get some money back on the way, awesome! If people just use it, enjoy it, and become healthier without me getting anything back, that's cool too! I have already got the reward of learning and enjoy every week myself!