On iOS, Simple is available in English, Spanish, French, German, Portuguese (Brazil), Italian, Swedish, and Turkish.
How to choose your preferred language in the app's settings on your device.
Go to your phone's Settings:
Scroll down and tap the Simple app icon:
On the next screen, tap on Language:
Choose the preferred language:
After that exit the phone's settings and reopen Simple. Your preferred language must be added to your device's Language list in iOS Settings first.