Jon Bentley tests: iPhone 6 vs. 6S

Jon Bentley compares the iPhone 6 to the new iPhone 6S

It's in the nature of capitalism and gadgetry that technology companies are always coming up with something new. They hope a steady stream of innovation will excite consumers and boost demand, keep the balance sheet healthy and the factories humming.

Sometimes these new products are revolutionary. The first HD camcorder I tried about a decade ago had me rushing out to buy it. I was stunned by the boost in picture quality over standard definition.

More commonly, new models offer a specification hike that's unspectacular but worthwhile. Nikon's current D5500, for example, is only a modest evolution of the D5300, and you'd be highly unlikely to upgrade from one to the other. But, if you're buying from scratch, or replacing a much older camera, you'll appreciate the newer model's lighter body, better battery life and touchscreen.

Occasionally, though, a new gadget offers so little extra that you may actually be better off buying its predecessor, if it's still available. Apple achieved this lamentable state of affairs in 2014 with the iPad Mini 3. With only a fingerprint sensor and a few other trivial specification differences, you would have been mad not to buy the older, otherwise identical, and nearly £100 cheaper, iPad Mini 2 instead.

So when Apple's latest iPhone, the 6S, appeared one could be forgiven for questioning whether we really needed it. Its cameras boast a few extra megapixels and there's a faster processor, an extra gigabyte of ram and a new-fangled 3D Touch screen. But it looks the same as the 6, which is still available and a great phone by any standards. And the 6S is considerably dearer - it costs £80 more to buy outright for example.

The producers asked me to conduct some tests to compare the 6 and 6S, and find out whether the new model is worth the hype and the extra money. The results were pretty positive. The 3D Touch screen, which helps you access commonly used functions quickly by pressing relatively hard on the screen, helped me shoot a selfie and send it to a friend over a second quicker. 3D Touch will be used on more applications soon, so you'll be future proofing yourself a little by going for the 6S over the 6.

The 6S scored significantly better than the 6 when I ran 3DMark Sling Shot, an app which measures a phone's performance during high intensity graphic sequences. You'd certainly notice the extra zip in graphically challenging games, and everyday tasks like opening or switching between apps can be quicker too.

The 6S won overall in the photography tests. Its rear camera gave more detailed shots and more natural colours in low light, though there wasn't any difference in dynamic range (an area where the 6 was already notably good) and the front facing selfie camera seemed no sharper in spite of the extra pixels. Surprisingly, the 6S has a smaller battery but, under test, its battery actually lasted slightly longer than the one in the 6.

The positive news continued out on the streets of Birmingham. Though many people didn't spot the improvements, a small majority favoured the 6S when testing the cameras and playing games. Add in the likelihood that Apple will support the newer product for longer and the 6S was shaping up to be the best buy out of the two phones, if you can afford the extra cost.

It's not a revolutionary product. Unless you're a particularly heavy graphics user an upgrade from the 6 to the 6S probably isn't worthwhile. But if you're replacing an older iPhone, or moving to iOS, the 6S is definitely the one to go for. You probably won't notice the improvements all of the time, but it is a significantly better phone.