A few months ago, I started playing this strategy game in my Google Chrome browser. It's called Kingdom Rush by Ironhide Game Studio.
I got addicted to it and even tried harder campaigns/levels of the game!
Now, while looking for new apps for my iPhone, I found out that it's now free!
I think it was previously being sold at $1.99 (not sure). So now that it's free, I downloaded it immediately and here it is in my iPhone:
I will have to start from the first level, but it's fine with me! Happy freebie! :D