Ask HN: Personal liability releasing an app as a solo dev

Hi,

I've been working on an app to help studying math (sort of like a flashcard app), and I'm close to done a v1. I wanted to release it on the various app stores, with free and paid versions. The goal isn't to make a ton of money, just to make _some_ money from software I wrote.

The app itself is nothing controversial, but I wanted to know what I should do to protect myself before launching it, if someone sues me for failing their class or if an NPE claims to have a patent on "calculus on a mobile device."

I'm probably being overly paranoid here (USA based), but as solo a app developer what should I be thinking about before releasing?