Droneo 1.1 is now appearing in the (US) App Store! tell your friends.

Droneo is using Appirater, which works like this (from arashpayan.com

Now every time the user launches your app, Appirater will see if they?ve used the app for 30 days and launched it at least 15 times. If they have, they?ll be asked to rate the app, and then be taken to your app?s review page in the App Store. If you release a new version of your app, Appirater will again wait until the new version has been used 15 times for 30 days and then prompt the user again for another review.

It will go away if you want it to, but it will pop up when those time limits have gone off.