@Loïc Thank you for reaching out to us, As I understand you have queries on MDE for iOS devices.
Regarding deployment refer to this doc - https://learn.microsoft.com/en-us/defender-endpoint/ios-install?view=o365-worldwide#configure-supervised-mode-via-microsoft-intune
When a user sends a request to a website, the packets are sent through the local self-looping VPN to the ATP module, which analyzes the packets and website content for any malicious activity. - Reference
Regarding the remote services used by Microsoft Defender for Endpoint, these are cloud-based services that provide additional threat intelligence and analysis capabilities. These services include Microsoft Defender for Identity, Microsoft Defender for Office 365, and Microsoft Cloud App Security.
As for tools to analyze log/phone traffic, there are many options available, including Wireshark, Fiddler, and Charles Proxy. These tools can help you capture and analyze network traffic to better understand how Defender for Endpoint works on mobile devices.
I hope this helps! Let me know if you have any further questions.
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