Best app for scanning business cards?

Help! There are a lot of apps out there for scanning business cards into one's iPhone. (I have a 4S.) I'll need to export the information into a database; I use MailChimp for my newsletter, but I don't think you can import information that hasn't been provided by the newsletter subscriber him/herself.

Which apps do you like best for scanning business cards?

Can you recommend a simple way of exporting this information into a database that will be easy to access (perhaps has contacts in Gmail)?

Many thanks!!