At $9.99, Translate Keyboard Pro is on the expensive side for iOS keyboards. But it could be a very important tool for international travelers. Using this app, you type in one language, and the text changes into one of 91 other languages. Translate Keyboard Pro works with a ton of apps (Facebook, Twitter, iMessage, email, Viber, WhatsApp, Kakao, Talk, WeChat, Instagram, Snapchat and more). It might even help you learn a new language.