Is there a way to auto update every application on my wife's iPhone 4s?

She doesn't want to be prompted or asked for the iTunes password for every single update. She doesn't have that many apps and finds the little red prompt very annoying. She has unlimited data so that's not a concern. I can understand typing in your password to BUY an app, but to have to enter it for every iTunes transaction is really annoying. I have a Galaxy Nexus and can set it up to not give me update prompts. Is there a similar option for the iPhone?