[peterhartree]

Here's what I did for my Chrome extension [1]:

1. Searched the Chrome Web Store, Twitter and Google for users who had said lukewarm or negative things about another extension which addresses a similar user problem in a different way.

2. Searched the same places for people who were clearly interested in the topic of focus and email productivity.

I spent a day or so manually emailing several hundred people in this way. This initial push - and the events that it lead to (e.g. people I contacted recommending the extension to others) - got me 100 WAU within a couple of weeks (and lots of helpful feedback).

(I tried some other things which were much less effective. Listing sites, in particular, were largely a waste of time, though my Product Hunt submission came good when the extension was featured a few months later.)

[1] https://inboxwhenready.org