Startup Idea : Alcohol App to remain below legal driving limit

An app that counts and calculates the amount of standard drinks you are consuming and lets you know when it is okay to drink again or drive. Generally, men are allowed 2 standard drinks in the first hour then 1 standard drink per hour after to remain below the legal driving limit. However, majority of alcoholic drinks are more than 1 standard drink (ie. normally 1.3-1.5 standard drink). This causes drivers to blow over the limit even though they have followed the guidelines. The app will allow users to select what they are drinking and a timer will show when they can have another drink or their blood alcohol limit will be below the legal driving limit.