Learn how to Snapchat with your friends and family using this app. Snapchat is a mobile app for Android and iOS devices. One of the core concepts of the app is that any picture or video or message you send - by default - is made available to the receiver for only a short time before it becomes inaccessible. Your grandchildren may have never lived in a world without social media. SnapChat would be the social media if you want to connect with those under 30 years of age.