looking for a talent Ionic/Cordova Developer

I want to add this simple function, I will share ionic source, and you can work with firebase db. - One member can only login once. - If another member logs in with same username and password, the first user will be logged off. more explaining: A member is login using X user name in A device. --> when log in, it will store A device name in firebase db. B member is login using X user name in B device. --> when login it will remove A name in firebase db, also store B name in firebase db. also send order command to A device to log out