Hey @Ananiya,
Based on my experience, if your app was built properly based on optimizing your screens performance, and data loading, it’ll be able to handle thousands of users without noticing any issues.
I have apps that are running +20k and +40k users and they’re performing really well. It’s all about how you build the app to be (Simple To Use), and avoid complexity by organizing your database properly, avoiding too many screens, and maintaining smooth data flow between screens.
For more tips about improving your app’s performance & make sure it runs smoothly on launch, I recommend checking those articles: