We have released a few languages on our IOS and Android mobile apps. In order to change the language the app is currently using, you will need to go to your phone's settings.
If you go to Settings > General > Language & Regions (IOS), or Settings > Languages (Android) you will be able to see all the languages that have been added to your phone.
Removing the language from the list, should prevent the app from defaulting to it. Please keep in mind that as we release new languages, the app will default to the first language we support on that list. If you prefer to always use the app in English, please make sure that English is placed at the top.