For anyone willing to share tweets when they are not online, various web services exist to accomplish this task (I had also built an open source app: Scheduled Tweets -not updated anymore-).

Tampon is a free and open source alternative (that is inspired from Buffer) that schedules tweets.

It is a Backbone.js application that uses MongoDB for storing the data and has a PHP-based REST API.

Tampon

The application allows creating a schedule with multiple entries and auto-sends your tweets at those periods.

Tweets entered can be re-ordered with drag 'n' drops or, optionally tweeted instantly.

Considering it is open sourced, Tampon can also be a good starting point for creating a feature-rich, customized version.

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