In the late 1990's Picarta and Britannica, the digital encyclopedias were making their way into our CD collection. We would use them when writing papers for biology or chemistry in primary school. Then, in 2000 we saw all that information move online and Wikipedia quickly became our new source of knowledge. Now, ten years after Wikipedia new knowledge sharing apps are trying to satisfy the thirst for knowledge of thousands of people looking for answers to their questions. 
These are the App Awards for the best knowledge sharing apps. 

Best feature: Freebase

Knowledge sharing is nothing if there is no knowledge to share. Freebase Gridworks, now known as Google Refine, helps users clean messy data, transform it from one format to another and linking it with Freebase databases. This can help users make quick work of their data, getting a clear and consistent terminology throughout their research. It is a great feature for anybody trying to do a research with data having different labels.