PHP Tweet Scheduler -- 2

We need a PHP application which allows users to sign into their Twitter and GNU Social/StatusNet accounts and schedule tweets to be posted at a later time. Scheduled tweets can be changed and removed at any time before they are actually sent. Tweets that have already been sent will be stored in an archive. Users will be able to remove individual tweets as well as the entire list. Scheduled and archived tweets will be exportable in JSON and XML formats, with simple filtering such as date filtering. All of those operations shall also be possible through HTTP POST requests to an API. For this purpose, a unique key must be generated to authenticate users, with a simple way to change the key should it be compromised.