Change the locale (language / country / variant) of your Android device. That's all. This app does one thing and does it well.
Note: This app will not work as-is for Android 4.2 or later. Since Android 4.2 the permission required to change the locale has been restricted to system apps only. It's possible to give the app permission if you have a rooted device either by granting the permission with the 'pm' command (pm grant com.sweetiepiggy.everylocale android.permission.CHANGE_CONFIGURATION) or by moving the apk from /data/apps to /system/apps. An app like "/system/app mover" might make this easier: https://play.google.com/store/apps/details?id=de.j4velin.systemappmover
There are no ads. The only permission required is CHANGE_CONFIGURATION, which is needed to change the locale.
Take note that if a locale is not supported by your phone or your app then you may not notice any change.
Feedback and suggestions for improvement are most welcome.
This is a free and open source app. The source code is available under the GPLv3+ license at https://github.com/sweetiepiggy/Every-Locale
If you are interested in helping, it would be much appreciated if you would take the time to translate the words below into your own language. Please email the developer at firstname.lastname@example.org