The American obsession with the iPhone is complicated, as most love-hate relationships are. It sometimes seems like a talisman so magically powerful that we can't fathom living without it. The iPhone, and its smartphone brethren, enable pictures that can almost instantly be posted on social media, play a video game, watch a video, listen to music, send a text, check email, surf the internet, catch up on on the news, get directions, tap to pay at the checkout stand. Oh — and, every once in a while, it can even make or answer a phone call. At other times, it seems like a drug-dealing pusher preying on our weaknesses and worst impulses while deepening our addiction.

A key online learning system used by thousands of schools and universities is back after a cyberattack knocked it offline, creating chaos as students tried to study for finals. A cybersecurity threat analyst says a hacking group called ShinyHunters claimed responsibility for breaching Canvas. Instructure, the company behind Canvas, said late Thursday that the system was available for most users. An expert says the hackers posted online that nearly 9,000 schools worldwide were affected, with billions of private messages and other records accessed. Teachers had to find workarounds to help students study for exams and submit final assignments, and some schools pushed back finals.