Not everyone has the brain space to spare in order to remember how many teaspoons are in a tablespoon or the formula for converting Fahrenheit to Celsius — let alone that morning’s exchange rate for dollars to yen. For those of us who aren’t pub-quiz champions, Amount is an app that will put all of those quick conversions at your fingertips. It’s undoubtedly a handy tool for international travelers or serious bakers, and the app lets you save favorite conversions on a handy shortcut list. But ultimately, it’s a niche app and you may balk at having to pay any amount — even 99 cents — when it’s just as easy to pop your conversion question into your nearest search engine. 99 cents, for iOS devices.