A few weeks ago, I wrote about an app that looks at you through the Mac’s webcam, and as soon as it detects a slouching posture, it sends a notification . The app even logs all the instances and provides a daily posture score. It was an open-source app , but soon after it was shared on Reddit by the creator, a huge chunk of fellow Reddit lurkers started asking about how it processes and stores data. Those were existentially valid queries. After all, you are giving an app access to the camera, which can monitor you and the world around you in real-time. Is there a backdoor that allows a bad actor to take a sneak peek? What else is the app logging in the background, and how much of the audio-visual stream is being relayed or stored on an external cloud server? Thankfully, the app works fully online, and all the processing happens locally on my Mac. But the sense of unease prevailed. That pushed me to try creating my own software.…