OmegaT - OmegaT is a free open-source translation memory application for professional translators written in Java.
Lokalise - Localization tool for software developers. Web-based collaborative multi-platform editor, API/CLI, numerous plugins, iOS and Android SDK.
Crowdin - Localize your product in a seamless way
Phrase - A platform offering AI-powered translation tools for localization at scale.
Transifex - Transifex makes it easy to collect, translate and deliver digital content, web and mobile apps in multiple languages. Localization for agile teams.
POEditor - The translation and localization management platform that's easy to use *and* affordable!