We recently released our first translation options on the mobile app! Currently, the language options are English, Spanish, and French. Please note this is only for UI elements at this time, and not for foods and recipes.
To use this option on the app, go into Preferences in the lower right, scroll down to the Account section, and select the Language option.
On the website, the easiest option at this time is to use a browser like Chrome that can auto-translate the page.