BAC iPhone App

Law Firm seeking iPhone App that would calculate Blood Alcohol Content (BAC) based on weight, time, volume, type of drinks ingested, and current time. (Calculation formula can be provided). Attractive and friendly user interface required. App is to be accessible for dowload from Law Firm's webpages and display an advertisement for firm. Also to include the ability to include additional attorneys based on zip code and protocol to allow uploads from central database that contains and update advertising attorneys with relevant zip codes. Basically, law firm only represents DWI clients in several counties of North Carolina. Want the ability to include attorneys nationwide who service different counties. Those attorneys need to be able to be updated and stored locally and uploaded to App periodically.