Engineer’s Notes: QR Codes & Stress-Free Travel

Not so long ago, I used a mass transit service. A ticket inspector came and asked me for my ticket. I pulled the phone from my pocket, unlocked it, launched the ticket app, clicked “Show my QR code,” and…

Photo by Andrea De Santis on Unsplash

My heart began to race as the QR code was loading longer than I anticipated. I glanced at my surroundings, and to my horror, I realized we were in a tunnel. Thus, at least…