@Sylvain Simpson,Thanks for posting in Q&A.
Based on my research, Microsoft Intune Plan 1 core capabilities are as follow.
1.Cross-platform endpoint management
2.Built-in endpoint security
3.Mobile application management
4.Endpoint analytics
5.Microsoft Configuration Manager
With this license, you must enroll the device into Intune before you can manage the device, deploy the app and manage the app.
Microsoft Intune Plan2 license is a lightweight VPN solution for iOS and Android mobile devices that does not require device enrollment, which can deploy some specific apps to devices that are not enrolled to Intune
https://learn.microsoft.com/en-us/mem/intune/fundamentals/deployment-guide-enrollment-mamwe
https://www.microsoft.com/en-us/security/business/microsoft-intune-pricing
Please purchase the license you need based on your actual needs.
Hope it will help.
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