The interface is very smooth for this app. Easy to use and not overly clunky or crowded (an issue I found with a few comparable apps here).
This isnt going to give you a list of every cocktail known to mankind. But its got a super solid list of anything youd realistically want to make. Plus, I really like the feature in which you can select the ingredients you have on hand, and itll tell you what you can make (there may be one or two ingredients in a suggested cocktail that you dont have, but chances are these are basic things like limes or tonic that you really ought to have anyway).
So overall, yes. I highly recommend this app.
Norse Welsh about Cocktail Flow - Drink Recipes