Here are the details from Nokia about the developer survey:
Nokia wants to hear from you!
Updating your app benefits everyone. The more you work on it, the better the experience becomes. By extension, the people that download your apps will be happier, too, because they will see all of the work you are doing. If you’ve ever published an app to the Windows Phone Store, Nokia wants to hear from you. As part of their ongoing commitment to and support of the Windows Phone community, they want to know what you think about Windows Phone - and find out how they can help you continue to develop, update and publish apps to the platform.
To take part, go to this website and complete the quick survey. Not only is it a chance to let Nokia know your thoughts on Windows Phone, Nokia UK and Nokia, Inc (US) are running a prize draw for local developers. It puts all you UK and US developers, who complete the survey by 20th September 2013, in with the chance to win a Nokia Lumia of your choice, a set of Nokia JBL Wireless Charger speakers and $100 PayPal credit!
Click here for full UK resident prize draw terms and conditions and click here for US resident prize draw terms and conditions.The survey closes on 20th September though. As there’s only a limited amount of time to get involved, so don’t delay!
A link to this survey also gives us an excuse to share some Windows Phone Store app activity number from our Windows Phone Store tracker. In the last seven days approximately 1450 apps were added, roughly 2000 apps received an update, and around 391 apps had a price change. There's been a gradual pick up of app activity over the summer, likely a consequence of the increasing number of Windows Phone users.