Open Source Alternative For Buffer – Circular
Buffer is one of the most popular apps for managing multiple social media profiles, scheduling posts and more.
Circular is an open source alternative for Buffer that is built as a Backbone.js app with a REST API written in PHP that stores data in MongoDB.
It only works with Twitter where you can add a list of tweets and they will be sent on the date-time defined.
Multiple accounts are supported and a bookmarklet helps using it easier.
P.S. The app can also be used and tried with the hosted version.