Algo by AirDev - Turn a Google Sheet model into a web app in 5 minutes
The Ultimate Google Sheet Toolkit - We put together a curated list of templates, videos, and tutorials that can help you build your analytics expertise.
SpreadShare - Explore community-curated spreadsheets.
Google Sheets + MonkeyLearn - Power up your Google Sheets with text analysis
Sheetsu - Turn Google Spreadsheet into API
SheetHacks by Polymer Search - Discover the best tips & tricks for Google Sheets & Excel