Smart Apps for Kids
I subscribe to Free App Alerts from Smart Apps for Kids, which means that every day I get a heads-up on well-rated free apps for kids. Some of the apps are free because there are in-app purchases later on, and sometimes the publisher/developer has a giveaway. Most apps are for iPad, but I have been able to find some for my Kindle Fire and Galaxy Tab. The site also runs giveaway and reviews and you can search by age range. App developers can submit their wares for review there as well.