I got frustrated with the current market of ambient noise and focus mobile apps. Almost every tool out there has shifted toward heavy cloud architectures, tracking user data, and hiding simple background audio play behind monthly subscriptions.
Another massive issue I found was "loop fatigue" when your brain registers a flat, repeating 30-second rain track, it breaks your flow state instead of sustaining it.
To solve this, I built NeuralFlow on the Google Play Store.