It's a fantastic android app . You can create "recipes" to perform tasks for you. Most of mine are based on where I am.
For example, I have one that automatically turns my ringer off and sets my phone to vibrate when I get to work. Another that turns my wifi on/off when I arrive/leave home.
There are bunches of pre-made recipes you can use or you can create your own. It's also very user friendly.
Edit: I believe there is also a dedicated subreddit, though I think it's named after the previous title, IFTTT