Babelgum Translator is an in-line translator that lets you learn foreign vocabulary from the web content you love through a Share action extension that extracts text from web pages in Safari.
TransKey is a translator that lives inside your keyboard. That way, you can translate messages without switching applications when chatting with someone in WhatsApp, iMessage, or any other app!
RedCookie is an app that lives in your Mac's menu bar and is a convenient and faster way to get things translated.
Tragl is the smartest hands-free live translator