One of the more common uses of Twitter for me is to monitor “back-channels” at events (often events I can attend, but more often these days events I am unable to attend).
Unfortunately Twitter’s search capabilities cease to be useful after a little while and so it is very handy to be able to create an archive for the events ‘hashtag’. There used to be a number of tools in the early days, but mainly because of Twitter’s changes to policies and very unfortunate morphing into a closed ‘media-publishing’ platform, the developers of such tools were forced to discontinue their services.
Here is IMHO the best remaining tools I have found that still work:
This is an easy to used & fairly polished product which allows download of raw data.
This is a more involved, but open solution based on a Google Spreadsheet and can be modified to suit.