I am using my iPad with my local language (German). However, some apps I want to use in English.
The problem with the todoist iOS app (and probably Android too, haven't checked it yet):
The German translation is really bad. PLEASE: Either have a german professional translate it or leave it in English!!! Example: 'Posteingang' means 'Message Inbox'. I don't have any MESSAGES in my inbox! It's an inbox for tasks not for messages! So please just call it 'Eingang'. Another example: 'Unvollständigen'. WTH does that mean in this context? This word is an adjective!!!! Maybe you mean 'unvollständig' or 'nicht erledigt'. The used word is 100% wrong.
Again, PLEASE: Either leave it in English or have a professional translate it! Even better: Make it possible to set the app language to English. That shouldn't be too hard. It's possible in the Windows app.
Besides that: Great tool! Best I found for managing tasks. Thanks!