The app uses huge space on your computer, but once it is downloaded, you can verify transactions on the network independently, and don't have to trust anyone in the system. (kryptomoney.com)
This would probably result in more transactions on the network and would require extra data for each transaction. (bitcoinmagazine.com)
This is because there is not one, centralized party that is responsible for processing transactions on the network. (cryptonews.com)