Backstory: I've always wanted to get scuba certified. It's a hobby I love doing every time I'm on vacation but I hate going through the beginner course over and over again. I've been meaning to get certified but I put it off constantly.
The Idea: An app to encourage you to complete your hobbies.
Deep Dive: You would charge users to submit a hobby. They would receive 90% of their money back once they complete their hobby. You would send them timed reminders to complete their hobby. If you start in a specific niche, such as scuba diving, you would send users stories and trips to encourage them to complete their training.
Validation: The motivation field is huge! This is an interesting way to tap into an online motivational product.
Monetization: You would charge people $500+ but hold the money in escrow. Once they certify they complete their hobby you can send 90% of their money back. The whole point is to have their money be another motivator to complete their hobby.