https://feedletter.co/
FeedLetter - Simple feedback for your newsletter, websites and emails
A feedback system that your readers will actually answer.
for yourfeedlettersimplefeedbacknewsletter
https://www.feed-letter.com/
FeedLetter — Automagically turn your RSS feed into newsletters
Build and manage your subscriber list while your RSS feed automatically becomes newsletters. One tool, zero manual work.
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