The Twitter Archiver lets you easily save tweets for any search keyword or hashtag in a Google Spreadsheet. 

Enter a search query, or an hashtag, and all matching tweets are automatically saved in the Google Sheet. You can write simple queries, use boolean search or include advanced Twitter search operators to create more complex queries.

Twitter Archiver can be used for saving tweets around trending hashtags, conference tweets, your brand mentions, geo-tagged tweets, and more. It polls twitter every hour and pulls all the matching tweets into the Google Spreadsheet.

YouTube Tutorial: https://www.youtube.com/watch?v=MGU7azCYFpw

Twitter FAQ: https://www.labnol.org/internet/save-twitter-hashtag-tweets/6505/

Twitter Search Tricks: https://www.labnol.org/internet/twitter-search-tricks/13693/

Please watch the video tutorial to know more about the Twitter add-on and how it works with the Twitter API to fetch tweets for matching search queries. The Twitter app only uses your Twitter account for fetching / search tweets and will never post any tweets to your account.

The add-on is free though you can upgrade to premium edition to capture more search terms. The premium version also includes supports and polls twitter more frequently (every 10-15 minutes) to download new tweets. Go to https://digitalinspiration.com/GA05 to upgrade to premium edition.
Important Update: 
The Twitter Archiver app is temporarily unavailable due to changes in the Twitter API. We are working diligently to update our app and make it compatible with the new API changes. We understand how vital our app is to you, and we apologize for any inconvenience caused by this disruption.