With all the popular social networking websites there on the web, managing them from several different internet browser tabs or windows can get frustrated very quickly. These apps give you the ability to post on one or all of your connected accounts together i.e Multiple Facebook, Twitter or Google+ profiles together. These applications don’t require your passwords for social media accounts. OAuth is an open standard for authorization, which keeps your passwords safe on third-party sites and instead of giving the keys to your entire house, you’ve given a special key called ” that only opens one room which you want them to access.
Source: https://thehackernews.com/2013/10/security-breach-at-oauth-based.html