can i trade my iphone 6s 16gb in for an iphone 6s 64gb?

Yes. Apple will offer you $225 if it is in good condition. Please see the link for details. You could likely sell it for more on your own.

http://www.apple.com/iphone/trade-up/

Hi

You will make more money if you sell iPhone on Ebay .

Cheers

Beian

Hello,

No you can't switch a 6S 16GB and get a 6S 64GB for free. You can trade it.

Follow what elcpu has posted above.

Se estiver na garantia sim, mas por quê não troca somente o cartão de memória? Vá em uma revenda autorizada, apresente sua nota fiscal e troque. É mais fácil 🙂