@Tcoradeschi 

You can log in to your TP-Link account on multiple mobile devices simultaneously. As long as you’re signed in to the owner account, you can manage your Kasa devices through the Kasa app from any of them.

For your account security, we strongly recommend setting up screen locks (or even better, app locks) on all devices used to access the Kasa app, along with enabling two-factor authentication (2FA) for added protection. Making Your Account More Secure: Introducing Two-Step Verification (2FA) for the Kasa App