Im using this app since a year .i used to learn C C+ , and now im learning c# and Python. Its really cool app. They provide a platform where every individual and learn and grow and can help to learn others too.there support and service provide all this things to everyone. Simply someone can follow others person who are learning and have great knowledge. Its cover all topic and provide self learn and analysis with every topic we learn. And its very user-friendly and its also provide certificate after the complete test where anyone can clear as many times it need but need to complete all questions compalsary to get certificate.and cost of learn is free .