what is the purpose of rooting an android device
Rooting (Android) Rooting is often performed with the goal of overcoming limitations that carriers and hardware manufacturers put on some devices. Thus, rooting gives the ability (or permission) to alter or replace system applications and settings, run specialized applications ("apps") that require administrator-level permissions, or perform other operations that are otherwise inaccessible to a normal Android user. On Android, rooting can also facilitate the complete removal and replacement of the device's operating system, usually with a more recent release of its current operating system.
Samsung Galaxy Alpha Samsung Galaxy Alpha is an Android smartphone produced by Samsung Electronics. Unveiled on 13 August 2014, the device was released in September 2014. A high-end device, the Galaxy Alpha is Samsung's first smartphone to incorporate a metallic frame, although the remainder of its physical appearance still resembles previous models such as the Galaxy S5. It also incorporates Samsung's new Exynos 5430 system-on-chip, which is the first mobile system-on-chip to use a 20 nanometer manufacturing process.