Two apps reviewed by http://www.androidapps.com may be useful for winemakers using the android platform on their smartphone:

WineMaking Forum (Free)

The Wine Making Talk website and its related forum are popular spots for winemaking enthusiasts to read-up and discuss their art. This straightforward app brings the forum directly to your Android device. It could prove very useful if you’re out in the garage away from your laptop, or at a local store looking to purchase the necessary items you require to make your winemaking exploits a success.
 

Winemaker’s Toolbox ($1.99)

For two bucks, Winemaker’s Toolbox offers an awful lot, and will be invaluable to the home winemaker or even the professional vintner. It allows you to make all the calculations and conversions necessary, directly from your Android device, including potential alcohol, required sugar, fortification formulae, sulphur dioxide additions, acidity calculations and more. Check out the free Winemaker’s PA Calculator app if you only want to estimate the amount of alcohol in your wine both pre- and post-fermentation.