At any given time you can reset your Nexus 4 smartphone to the factory default settings, meaning you will bring your phone back to the same state as it was on a day when you took it out of the box.
Really great and free service where you can chat using a bunch of services like Skype or Google Talk within your web browser, meaning you don't need to install anything on your computer.
Google Chrome has a handy function where you can just paste an url or search term and you will go straight to the page or get the Google search results.
If you know how to sing or hum a song, but don't know the title or the artist performing it, you can use a midomi website which will help you find the the song.
If you want to put your video files online using HTML5 then it's recommended to have three different formats for a full browser support. Those formats are mp4, ogv and webm.
How many times did you hear a great song on a radio or in a YouTube video and really wanted to know the title and who's performing it? Let me show you the app that can find it out for you.