We've launched independent registration: Informant is now available to all Ruby on Rails apps, not just Heroku – check out http://informantapp.com and get your app hooked up in no time!
The Informant reports invalid form submissions (e.g. too many characters entered, invalid characters used) and reports common mistakes. I like the direction and it gets me thinking of other ways they might automate and quantify usability issues.
Cameron here, designer for Informant. I'll be keeping an eye on this thread to answer questions and such.
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This is awesome. I'm launching AnyMarket soon, the first real product I've built solely on my own, and this is definitely going in my bookmarks so I can come back to it when I prepare for launch. I'm sure there are a lot of errors that users will run into on signup that I just haven't thought of.
The Informant
Product Hunt
The Informant