
1 - Publish App1 in Azure Active Directory (Azure AD).
2 - From Microsoft Cloud App Security, modify the Connected apps settings for App1.
3 - From Microsoft Cloud App Security, create a session policy.
4 - Create a conditional access policy that has session controls configured.
Reference:
https://docs.microsoft.com/en-us/cloud-app-security/proxy-deployment-any-app
https://docs.microsoft.com/en-us/cloud-app-security/session-policy-aad