@NadaTech,

The Kasa app does not currently support guest accounts or sharing devices, however I would be more than willing to file a feature request with our development team for the feature. Guest Functions may become more important as devices powered by matter can actually be controlled by more than one controller at a time and could become complicated in households with multiple IoT networks.

For now, to give access to your Kasa devices, you have to share your TP-Link ID for them to log into their app with; or connect the device to a third-party service such as SmartThings, Alexa, or Google Home and share the devices with another user from there.