即使用户退出应用后，如何让用户保持登录状态？

I want to know how to make a user stay logged in even after the app is exited in react native, I am using restAPI to make a user login into my app and it's working fine but my problem is when a user exits the app user is displayed the home again but I want the app to display the welcome screen instead if the user has already logged in my app.I want to know how to make a user stay logged i