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    Greetings to all who have registered to OPF and those guests taking a look around. Please use real names. Registrations with fictitious names will not be processed. REAL NAMES ONLY will be processed

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  • Welcome to the new site. Here's a thread about the update where you can post your feedback, ask questions or spot those nasty bugs!


  1. Jerome Marot

    Warning! Beware of This: Yelp app is replacing restaurants phone numbers

    An interesting article if you order food through an app: https://www.vice.com/en_us/article/wjwebw/yelp-is-sneakily-replacing-restaurants-phone-numbers-so-grubhub-can-take-a-cut The Yelp app lists a restaurant’s direct phone number on the actual listing. But when a user clicks on the “Call”...
  2. Jerome Marot

    Contact tracing app.

    Apple and google are jointly developing a contact tracing app that would tell people if they were near a infected people in the past 2 weeks. The underlying mathematics are interesting. How do the apps work? A naive approach would be to store the position of the whole population all the time...
  3. Jerome Marot

    Warning! Beware of This: The story of Chloe (no photos).

    Chloe is an investigative journalist working for an international broadcast service; we will call the TV show she works for The Inquirer. She travels around the world to work with local journalists on uncovering stories that make the headlines: from human trafficking to drug cartels and...