This Is Not a Test, the survival RPG comic by Jon Richardson, recently went free. Players can now experience the comic though the addition of banner ads and limited lives that regenerate slowly.
If you want to remove the ads and recover your lives faster you can upgrade to the pro version for $2.99. The pro version also adds optional color background art, so if you've already purchased the previous color upgrade you automatically get pro.
You can check out This Is Not a Test for free on the App Store.