What are some alternatives?
When comparing Transifex and Localize, you can also consider the following products
Crowdin - Localize your product in a seamless way
Smartling - Website localization & translation
POEditor - The translation and localization management platform that's easy to use *and* affordable!
Feedly - The content you need to accelerate your research, marketing, and sales.
Lokalise - Localization tool for software developers. Web-based collaborative multi-platform editor, API/CLI, numerous plugins, iOS and Android SDK.
OneSky - Full Stack Localization Solution