What are some alternatives?
When comparing Localize and POEditor, 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
Smartling - Website localization & translation
Phrase.com - Phrase is a translation management system where localization teams come together to release translations faster and easier than ever before.
Poedit - Poedit translations editor. The best way to translate apps and sites.
Weblate - Weblate is a free web-based translation management system.