StumbleUpon is a sort of web browser that recommends articles, pictures, and other things across the web it thinks is relevant to your interests.
If you're bored of reading the same few blogs that you do every day, StumbleUpon will help you break up the monotony. When you first launch StumbleUpon it will ask you to log in or create an account with them. Once you do that, you will be asked to select topics that you're interested in from a list. The list is long but not too long.
Once you've picked your areas of interest, StumbleUpon will populate the front page of its app with stories it thinks are relevant to you. Stories are presented in a tile interface, following the design aesthetic of Windows 8.
Tapping on a story will bring it up full screen where you can like, dislike, and stumble upon more stories. You can choose to stumble upon content for all your interests or for one specific interest from a menu. StumbleUpon is a great way to waste some time and will point you to stories you may not otherwise have found.
There are some quirks with the app though. Some sites and pictures loaded off center and performance was mediocre. Loading stories in StumbleUpon took longer than expected, especially if you're used to the speeds of modern browsers.
Overall, StumbleUpon is a solid application that will help you discover content from across the web that are relevant to your interests.