Purify is the ad blocker, first one that came up when I searched the app store (it's 99 cents.) Heard them talking about them on Macbreak Weekly and how Safari flies once you block ads. It only works if you have ios9 installed. For me, speed would be half the reason to upgrade. 3D Touch is the other reason but I feel like it won't be that useful for another few months when most apps support it. I came close to going down to the Apple Store and impulse buying a 6S+ but called and they don't have any 64GB SG VZW. I think it's a no-brainer to upgrade if you have anything other than a 6/6+.