Portulator app for iPhone and iPad

This app is a utility that calculates the amount of spirits to add to a wine to make a port wine of a target alcohol percentage. The first tab is for fortified wines where the user simply inputs the wine volume, wine alcohol percentage, spirits alcohol percentage, and the desired port wine alcohol percentage. The result is the volume of spirits to add to the wine. The second tab is for port-style wines. With a given must volume and a starting and ending Brix, one can calculate the amount of spirits to add for a target alcohol percentage and a given spirits alcohol percentage. The tab also calculates residual sugar after the addition of spirits.