Most people will not want to make the CARROT app angry.
How do you keep the CARROT app happy? Considering that this snarky little app is, according to its creators, the world's first to do list with personality, you should get your to do list done. Going with the theme of gamification in tasks these days that people seem to positively respond to, every time you do a task on your to do list, you'll gain points through the CARROT app. These points will level the user up and grant cool little features like gifts, compliments, jokes and quotes. If you get lazy and stay on the couch all day, the CARROT app will start insulting, threatening and just generally being mean to you.
Time will tell how motivating it is to have your smartphone insult you, but humor has a way of getting the laziest people moving too.