Vivo developers modified there bootloader to used a different command for bootloader unlock/relock than the the stock android commands. And That's Why we need a modified fastboot binary to unlock bootloader of vivo. WARNING! It'll void your warranty. Follow the below steps to unlock bootloader of vivo phones :-
ROM Phone VIVO Y13L - ROM Android 4.4.4 ONLY MSM8916 Update Official ROM VIVO Y13L version: KTU84P -
If you own a Vivo Y15S smartphone and want to Install Stock Rom or Firmware on it to unbrick or fix bootloop issue then you can download latest Firmware for it. In this page we have shared step by step guide to Install Stock Firmware or flash file on Vivo Y15S.
Framaroot helps to root a wide range of Android smartphones by using the following exploits: Boromir, Barahir, Frodo, Legolas, Aragorn, Gandalf, Pippin and Farahir.Using this application to root your Android smartphone or tablet is quite an easy task, as all you have to do is download the app, install it in your device, open it up in your Android device and then click on any of the exploits.
Nov 06, 2015 · firmware update vivo Y15S & Y31 (latest vivo mobile software update )
Vivo Y15S smartphone was launched in August 2015. The phone comes with a 4.50-inch touchscreen display with a resolution of 854x480 pixels. Vivo Y15S is powered by a 1.3GHz quad-core processor.