What are some alternatives?
When comparing Localize and Smartling, you can also consider the following products
Transifex - Transifex makes it easy to collect, translate and deliver digital content, web and mobile apps in multiple languages. Localization for agile teams.
Crowdin - Localize your product in a seamless way
Phrase.com - Phrase is a translation management system where localization teams come together to release translations faster and easier than ever before.
Feedly - The content you need to accelerate your research, marketing, and sales.
POEditor - The translation and localization management platform that's easy to use *and* affordable!
Lokalise - Localization tool for software developers. Web-based collaborative multi-platform editor, API/CLI, numerous plugins, iOS and Android SDK.