This is really awesome! I've been working with Joost for quite some time now. We developed our first app together when Joost was 13 or 14. Joost also developed my latest app http://www.routeshare.com.
I can say that Joost is a really good design driven developer (I sent his code to other developers a few times). Joost might be the best developer I know, well the best of all developers that wants to become an accountant.
I really like Joost finally worked on his own project and put together such great quality software. Download Notifyr and remember: Joost is 17. So cool!
I hope this makes him filthy rich and he changes his mind about becoming an accountant.
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