You know bro, You can't just upgrade it in simple way. BECAUSE IT IS THE CHIPS INSTALLED THERE INSIDE YOUR PHONE. IF YOU WANT TO FORCE TO DO THAT, IT'S SIMPLE. BUY A CHIPSET THAT YOU CAN INSTALL ON YOUR PHONE JUST LIKE $299. AND REMOVE THE "4.1.2 JELLYBEAN" ANDROID CHIPSET AND CHANGE IT TO THE ONE YOU BOUGHT. That's simple!!!