Locale Themes for Android Application size reduction

Android since its inception has evolved from running feature phone applications with fewer locale support to today’s feature rich applications supporting diverse set of locales for different geographies and culture. To support a locale, Android app developers add text translated to that locale as string resources in the application source. Each locale support added to an application increases the size of the Android Application Package (APK). Our paper explores a novel solution to reduce the footprint of locale specific resources by packaging them as Runtime Resource Overlay (RRO) APKs and applying them as a locale theme during the device runtime without developer intervention or compromising user experience. Our method is applied to apps in system partition of OEM Android devices, as free space available in system partition is crucial for the number of features and software upgrades that can be provided. Experiments show that footprint of string resources in the APK reduces by ~60% for a typical OEM Android app supporting 90 languages.