Microsoft showed off facial recognition software last week at Build 2015 that can guess a user's age, with the goal of highlighting how its new cloud applications can analyse large amounts of data.Hosted at how-old.net,the application was made in just a day using new face detection rules for building software.Creators Corom Thompson and Santosh Balasubramanian have made the APIs how-old.net uses available online through Bing and Microsoft's Project Oxford.The face detection API, which can be used for mass video analysis, takes in the exact location of an image's eyes, mouth, eyebrows, nose and lips, as well as face dimensions.The app uses the characteristics to group people, as well as identify one person in two or more photos.