Microsoft Rules for External and Guest Users in Power Platform

• Power Apps and Power Automate are primarily designed for in-house apps and workflows; use by individuals outside the tenancy may have limitations and/or incur extra costs.
• Power Platform line-of-business automation that requires access by guest users may require full licenses for those users.
• Pages is the easiest way to grant external users access to apps without purchasing them licenses.

Some Power Platform services—Power Apps, Power Automate, and Power Pages—allow users from outside a tenancy to access (and even edit) projects at different levels. Since Power Apps applications and Power Automate flows target in-house line-of-business solutions, they could present challenges when automation requires actions from users outside of an organization. Microsoft has remedied this situation by offering licensed access by guest users. Power Pages also allows anonymous, unlicensed usage and that might be the best solution for some scenarios where non-internal users must access them.