Last September the CEO of Twitter had announced they were developing a feature that would allow end users to download all their tweets.
As reported by Techcrunch, in a talk on the role of Twitter in the future of global communications and democratized access to information, which was developed at the Ford School of Public Policy, University of Michigan, Costolo was asked about this topic to which he replied that by year's end users can download all of their tweets.
But perhaps not so well, as well as the above said engineers are working on this, every time he speaks publicly about it, get angry and the reason for the anger is that they believe they will be able to finish on time .
So do not get your hopes up, but the good thing here is that the development is still alive, do not put aside, and assuming you do not finish in time, maybe we should wait a little longer, but the important thing is that we have the ability to support all our tweets.