How to import photos from iPhone 4s to iPhone 6 when computer won't read iPhone connection for export

I just switched wireless carriers and was not able to save all of the photos on my old iPhone prior to the switch. I tried to hook my old iPhone 4s up to my PowerBook G4 to export the photos, but my laptop is not reading the iPhone. I think it's my operating system & I even ordered Snow Leopard to try to help myself out here and be able to access these photos. Snow Leopard wouldn't download because it said I needed a Mac with an Intel processor. What are my options here? I would be heartbroken if there is no way to export my photos from my old iPhone to my computer or my new iphone.