Less than 3 months later I received a terrifying email from Disney's legal department, summed up by the last line:
"...Please immediately remove and discontinue all use of Disney’s intellectual property displayed in your app in the iTunes Store, and by October 16, 2011, send me written confirmation that you have complied with the foregoing and will not resume the unauthorized use of any of Disney’s properties."
My first thought was that I had wasted a huge amount of time with app development. I had also invested all of my money into these 2 apps. I started thinking that maybe I should do some schoolwork and stop focusing on business. That lasted for 5 minutes.
What I learned from this + how it actually helped my business:
1) "It is better to beg forgiveness than ask permission." Disney never would have given me permission to use their trademarked names. Luckily I didn't even know to ask and my business was launched.
2) My failure was in developing 2 very similar apps. Disney showed me how easy it is to wipe out an app regardless of how much time you put into it. Since then I've focused on creating as diverse a portfolio of apps as possible.
3) I may have been fine with $100/day if Disney didn't step in. I was so scared about the volatility of the app market though, that I developed apps nonstop for months.
4) I made enough money from the first 2 apps to fund at least 5 new apps. Profits from those 5 apps funded the next 5 and so on.
The point is to fail as fast as possible and learn even faster.
Also, I forgot to mention why I wasn't completely disappointed when the apps were initially removed. The reason (I'm pretty sure) was that my apps were destroying Disney's apps in keyword search rank. This meant that when you searched for their keyword, my apps came up first. That was a satisfying win for me.