Will this work?

Ok so one question, say I bought an app on my account and I want to put it on my friend or brothers laptop, simply Id login with my ID on their app store and download it, will it work that easily? Once im done if i log out and he logs in with his ID will the app still work and everything be run correctly? If a new update comes for the app, will he need access to my password/account in order to do so?