Check it out at http://kiteedu.com !
Dialoggs is a social conversation network that can be used in a number of ways. See my explanation at http://amirmalik.net/2012/04/27/introducing-dialoggs if you're interested.
With ~100 users (~20 active/day), it's been great iterating on the product and seeing user feedback first-hand. Our app is incomplete with obvious bugs, yet we still launched. People love it and understand that we're human, and it's still a work-in-progress.
Don't wait for perfection that may never come, just launch.
https://infrastructure.personalmba.com/
I wrote the guide, produced the PDF using a nice third-party template with a few custom modifications, and wrote the entire sales app from scratch. This project is the first time I've used Stripe and Mailgun. The entire project took less than a week, and is on track to net five figures in the first month of sales.
Quite like the idea of this thread - I've started to try and release something every two weeks until I find something that I really want to put all my time into.
Its a long-form travel magazine. Our second issue is coming out in July and next up is gaining some advertising. Should be fun.
[Mac App Store]: http://itunes.apple.com/us/app/reddit-notifier/id468366517?m...
Also shipped a much-improved version of the Mac app itself... but that's still waiting for review from Apple. So I suppose that doesn't count for April :0
It's currently pretty basic, but I have lots of neat stuff on my todo list -- should be a fun ride.
(I don't have it anywhere to share, and since it's VB I'd be a bit ashamed to, sorry)