Something minor, but that causes an argument, which leads to...

Sarah frowned at her phone. "Well, the first thing I saw was a rule that said that cable repair guys are usually late, so I changed that to say that they're always on time. It didn't seem to do anything, so I don't know how this app works."

Josh was confused too. He wanted to figure out what to do about the app, but Sara had just said something so dumb, he couldn't let it go. "What are you talking about? Cable repairmen are always on time. They're known for being punctual."

"Have you started smoking crack?" asked Sara. "Everyone knows those guys make you wait around forever, and half the time they don't even show up!"

"That's bullshit!" said Josh, not realizing that only Sara could remember the way the world was before she made the change. "Why do you always do this?! When you get something wrong, you just make up some shit and try to convince me it's true!"

"You are so full of it, Josh!" Sara screamed, then she turned back to the phone. "This stupid app is broken. I'm going to send a copy to Anna and see if she can figure out the problem."

"No don't!"

It was too late. The app was deleted off of Sara's phone as it was sent to her friend Anna. They continued arguing for an hour before deciding to never mention the app again.

Anna pulled her jet-black hair back into a ponytail and adjusted her glasses. She knew that the ponytail and the glasses, combined with her Asian ancestry, made her look like a tech-geek cliche, but she didn't mind. Since she was a computer engineer, she'd pretty much accepted that she was living the cliche.

Her phone made a strange beep. She'd never heard that particular notification sound before, which was odd. She'd explored everything her phone could do within an hour of buying it.

"What's this?" thought Anna as she looked over the app. "It's got a note attached. 'What the hel is ths, got it from stupid bfriend.' Well, that doesn't narrow it down, every girl I know thinks her boyfriend is an idiot."

Anna scrolled through the app, but there didn't appear to be any instructions. She tried to read through all the rules to see if there was a pattern, but there were thousands, maybe tens of thousands.

Then Anna saw one rule that stuck out. She couldn't help editing it.