As a Hive Application developer Implementing a secure solution for authentication (signing-in users), storing and protecting user's credentials, and broadcasting signed transactions to the Hive blockchain (providing access to user's private keys) can take significant effort. You must make sure to follow best practices and standards, and keep your implementation safe and up to date.
By implementing Hive Authentication Services support into your application, all you have to do is to ask for a username, period!