As a European who is comfortable with English, I find myself setting apps' language to English, exactly for this. My language (any language the author doesn't speak, I suspect) tends to be half-translated at best, or worse, "translated" into a hodgepodge of Slavic languages (Czech/Polish/Slovak/Croatian/Russian, whoever was at hand I assume), or worst, copypasted, word by word, through GTranslate, leading to bizarre results: e.g. "exit" in English has an "app" context, a "public transit" context, a "highway" context, and several others; most apps just pick one at random: "Press Back twice to exit the app" becomes "Push backbone twice to walk out of the app", and "Take Exit 24" turns into "Pick up the end 24"