This existed as a thriving third-party ecosystem, before Twitter dismantled it, http://www.mathewingram.com/work/2015/04/30/twitters-multi-b...

"Last year, Twitter effectively admitted that it needed third-party developers ... For anyone who had worked with Twitter in the past, however, this was a little bit like Fox Inc. asking for chicken volunteers to help it build a new hen-house. As far as I can tell, there’s little or no evidence that Twitter’s outreach program is working. What would Twitter be like today if it had embraced its ecosystem and tried to build on it instead of cutting it off at the knees? ... I think it would have a lot more goodwill to spend — both with developers and with users — than it does now, and I think many aspects of the service that it is now trying to build up, including smart recommendations and curation, would be a lot better off with outside input than they are now."