Hi!
In next few weeks I'll be start to advertise in countries like Turkey, Spain, Russia.
I don't speak any of this language that's why I wan't to find a way how to establish an effective system for banners and other marketing materials localization.
For app description and APK files is option in Google Play for buy translation with just a few clicks.
What about massive amount of banners? How to deal with that?
test your banners/angles in a language you are comfortable in (or just 1 of them)
Take winning 5-10 banners and translate them
once a campaign is profitable you can keep testing new banners