Hello @Barragan Vargas Saul Cesar Augusto
Thank you for reaching out. Based on the question I understand you want to know about Activity timestamp of devices.
Activity column lists a timestamp-related property which can be used to managed lifecycle of devices registered in the tenant. This property is referred to as ApproximateLastLogonTimestamp or activity timestamp and can be found in All devices blade or from devices blade of respective user's profile.
Any device authentication sign-in activity to Azure Active Directory using the device ID is a valid activity and the timestamp is updated. If a device is active, it will have a timestamp within the last 14 days.
The evaluation of the activity timestamp is triggered by an authentication attempt of a device. Azure AD evaluates the activity timestamp when:
• A Conditional Access policies requiring managed devices or approved client apps has been triggered.
• Windows 10 or newer devices that are either Azure AD joined or hybrid Azure AD joined are active on the network.
• Intune managed devices have checked in to the service.
If the delta between the existing value of the activity timestamp and the current value is more than 14 days (+/-5 day variance), the existing value is replaced with the new value. Additional details about this property is also documented in below article.
How is the value of the activity timestamp managed?
I hope this answers your query.
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