There are dozens of free currency-converter apps, but Oanda stands above them all for its reliability and depth of data. To calculate exchanges between more than 190 currencies, the app pulls from interbank market rates—what banks use when trading money. For even greater accuracy, the app also adjusts results to reflect the specific transaction type (credit card or cash) you select. Android, BlackBerry, iPad, iPhone. Free.
Foreign-language mix-ups can make for some serious travel stress. iTranslate—basically a digital phrase book—comes to the rescue. The app includes 52 languages and translates faster than you can say, “Huh?” Just type in the perplexing phrase and iTranslate displays it back in your language of choice. (The app requires Internet access, but you can store key phrases for future Wi-Fi-free reference.) Android, iPad, iPhone. Free.
Clothing size is unreliable from label to label—and country to country. Now men and women can shop with confidence by using 3-month-old Convert Clothes. When you roll a dial to pick your U.S. size in four categories (clothes, shoes, pants, and bra), the app’s simple interface spits out the corresponding numbers for eight countries, including Japan and France. Whether anything will actually fit is another story. Android, iPad, iPhone. Free.
FOR EVERYTHING ELSE
Traveling can seem like one long equation, from figuring out temperature (Celsius?) to assessing how much gas is left in your tank (liters?). Conversion-catchall Convertbot does the math for you. Spin a wheel to select one of 22 categories—time, speed, even data download size—then type in the amount. The app instantly converts the figure into the desired unit of measure. You’ll never go over the baggage limit in a foreign country again. iPad, iPhone. $2.
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