Differential Privacy

When we collect a lot of personal data, say via the US Census, the goal is to glean important aggregate information and statistics, while somehow preserving the anonymity and privacy of the individual respondents. There’s a rigorous mathematical process for doing this – that’s actually not that hard to understand – called Differential Privacy. I’ll explain how it works.

In the news: iOS has a new location privacy setting; Google confirms it’s rolling out AI to Gmail; Windows makes it much harder to avoid creating a Microsoft Account; WhatsApp is rolling out AI in Europe with no way to opt out; Switzerland is considering undermining encrypted communications; 23andMe is going bankrupt – it’s time to delete your data; France rejects a backdoor mandate; and finally, I have a lot to say about the US officials’ Signal chat debacle.

Article Links

1. [9to5mac.com] iOS 18.4 includes a new location services privacy setting for your iPhone https://9to5mac.com/2025/04/02/ios-iphone-new-location-services-privacy-toggle/
2. [forbes.com] Google Confirms Gmail Upgrade—3 Billion Users Must Now Decide https://www.forbes.com/sites/zakdoffman/2025/03/22/google-confirms-gmail-upgrade-3-billion-users-must-now-decide/
3. [windowscentral.com] Microsoft will force Windows 11 installs to use a Microsoft Account — confirms removal of popular setup bypass https://www.windowscentral.com/software-apps/windows-11/microsoft-will-force-windows-11-installs-to-use-a-microsoft-account-confirms-removal-of-popular-setup-bypass
4. [Bleeping Computer] WhatsApp’s Meta AI is now rolling out in Europe, and it can’t be turned off https://www.bleepingcomputer.com/news/artificial-intelligence/whatsapps-meta-ai-is-now-rolling-out-in-europe-and-it-cant-be-turned-off/
5. [techradar.com] Secure encryption and online anonymity are now at risk in Switzerland – here’s what you need to know https://www.techradar.com/vpn/vpn-privacy-security/secure-encryption-and-online-anonymity-are-now-at-risk-in-switzerland-heres-what-you-need-to-know
6. [arstechnica.com] FTC: 23andMe buyer must honor firm’s privacy promises for genetic data https://arstechnica.com/tech-policy/2025/04/ftc-watching-23andme-bankruptcy-sale-for-impact-on-users-genetic-data/
7. [schneier.com] The Signal Chat Leak and the NSA https://www.schneier.com/blog/archives/2025/03/the-signal-chat-leak-and-the-nsa.html
8. [eff.org] A Win for Encryption: France Rejects Backdoor Mandate https://www.eff.org/deeplinks/2025/03/win-encryption-france-rejects-backdoor-mandate
9. How Differential Privacy Works: https://firewallsdontstopdragons.com/how-differential-privacy-works/ 

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Table of Contents

• 0:00:00: Intro
• 0:00:28: Coin promo teaser
• 0:02:47: News preview
• 0:05:21: iOS 18.4 includes a new location services privacy setting
• 0:10:09: Google Confirms Gmail AI Upgrade
• 0:16:41: Microsoft will force Windows 11 installs to use a Microsoft Account
• 0:20:57: WhatsApp’s Meta AI is now rolling out in Europe
• 0:23:32: Secure encryption and online anonymity are now at risk in Switzerland
• 0:27:33: FTC: 23andMe buyer must honor firm’s privacy promises for genetic data
• 0:35:09: The Signal Chat Leak
• 0:53:05: A Win for Encryption: France Rejects Backdoor Mandate
• 0:56:14: Tip of the Week: Differential Privacy
• 1:06:20: Coin promo details
• 1:11:04: Merlin’s Musings topic
• 1:11:29: Looking ahead