In the Smart Life app, your devices and users are organized by home. This lets you add multiple devices to your app and manage them from one area, depending on where you are. To allow another person to use the Smart Home device, you will need to add them to the home.
Open the Smart Life app
Tap the "Home" dropdown menu
Select Manage Homes >
Select Edit on the location where you would like to add an additional user
Scroll to the bottom and tap Invite User
Enter the additional user's information and Send Invite
The user will need to download the Smart Life app, create an account, and accept the invite in their email. The new user can then access the location and the specific device you invited them to.