Taking a break from your always-connected computer and phone can do wonders for your state of mind. But what happens when you inevitably return to the digital realm, and find yourself in a world of advertisements, polarized comment threads, and endless sources of instant gratification? Good news: there's an app for that! Actually, there are a growing number of tools to help you personalize your internet experience to be better for your mental health -- and if there isn't one that meets your needs, you just might be able to code one yourself.