At some point I've looked at them, as I was looking for a cheaper Peak alternative. Absence of Asana integration was a bummer for us. We've ended up configuring notifications within Slack channels. Worked well for us.
Similar to http://www.usepeak.com (also listed on here). I personally haven't and can't see myself using services like these simply because most services (lets say, Trello) already provide notifications that work pretty well. Having said that, I am curious to know whether anyone finds this sort of app to be useful. I guess I assume they just end up being too intrusive and full of 'noise' but I'm open to being proved wrong.
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