XE.com - XE.com Inc. (XE) is a Canadian online foreign exchange services company.
Yahoo! Finance - Currencies Center - Currency Converter from Yahoo! Finance.
Tweetbot - Sync your timeline across your iPhone, iPad, and Mac. Mute tweets by user, hashtag, tweet source, or keywords (including regex). 3rd Party support for image, video, read later, and timeline sync services.
xCurrency - Smart Currency - A simple ads-free currency converter.
Valuta+ - Valuta+ is a super simple & free currency converter. The interface is fast and makes you convert exchange rates very easily. This app have more than 160+ currencies for you and is always updated.
Elk - The fastest way to convert currencies on mobile.