By Graham K. Rogers

This morning the two iPhone 7 models go on sale in Thailand and I have been looking at both devices. Anyone who likes photography will love what these have to offer, particularly the iPhone 7 Plus. Once set up, this has all the feel of the more recent models, although the changed Home button may take a little getting used to.

The Phone 7 has had a hard introduction. Even before it was officially announced, far too many commentators had already written it off in similar terms to how the "S" versions of iPhones have been dismissed many times. It is only when they devices are released, and users start to buy them, that these comments may be seen for what they are.

The other side of that coin is when the technical writers handle the device for a short time just after the official announcement and make pronouncements on the life-expectancy of the product. Some surpassed themselves with the iPhone 7, claiming that there was no change: same as the iPhone 6s and 6s Plus.

That is if you ignore the lack of a headphone jack, re-sited speakers (and 2 of them) a Home button that feels different. more haptic feedback, and the A10 processor. To be more precise, that is the A10 Fusion with 4 cores: 2 for power and 2 for efficiency. Looking at an Apple product is like watching an iceberg: you only ever see a small part and the most significant sections are hidden.

I will concede that the basic shape was similar to the iPhone 6s, but all the commentators ever have to do is look at the technical specifications on Apple's website and read the information.

The iPhone 7 is no leap into a new world, but a good example of the evolution of the device: softly, softly, rather than go for major changes, some of which may flirt with disaster. Apple doesn't rush.

I unboxed the iPhone 7 Plus first. This is to be my prime device. I had hesitated with the iPhone 6, but when the iPhone 6 Plus arrived that was my first choice and now I am too used to the larger screen area, although I like the smaller iPhone SE for its feel in the hands.

A lot of buyers have gone for the Plus versions of the iPhone 7 in several countries. Although the device goes on sale here today, all of the carriers reported last week that the iPhone 7 Plus is fully subscribed; and the 256 GB version of the iPhone 7 Plus was sold out first.

Retail outlets may have a few for sale, but these are usually pre-ordered too. The best bet for most here who have not yet staked a claim is Apple's online ordering: when I have bought iPhones this way in the past, it has only taken a few days; and the purchase is delivered to the door. Why line up?

There are now 5 colour options (Rose Gold, Gold, Silver, Black and Jet Black) with three capacities. Prices here are:

iPhone 7

• 32GB - 26,500 baht
• 128GB - 30,500 baht
• 256GB - 34,500 baht

iPhone 7 Plus

• 32GB - 31,500 baht
• 128GB - 35,500 baht
• 256GB - 39,500 baht

I was interested to see the accessories in the box. There was a great hoo-hah when it was just suspected that Apple was going to drop the 3.5mm headphone jack in favour of the Lightning port. I have been in favour of this all along. Apple was smart to include a headphone jack to Lightning adapter in the box, so that those with higher quality headphones could carry on using them.

The real direction will be wireless. Although the new Air Pods are not yet available, those who have tried them are impressed with the sound output; and all that drivel about them falling out of the ear was made with no experience of using them. They don't.

Having tested a number of health-related devices that work via the 3.5mm jack, I was concerned about how they would work, so as soon as I could, I tried the G-Smart Blood-Glucose device using the Lightning port on the iPhone 6s Plus. There was some attention to output and volume settings, but a quick jab of the finger and my blood was checked. When I later connected the device to the iPhone 7 via the adapter, the results were identical. I did not doubt that Apple would have that covered.

Setting up was easy enough - I have done this a few times before - but I always forget to make the WiFi password available and that causes a rush to find it. Once done, passwords and authorisations all set. I backed up the iPhone 6s Plus to iCloud and used that as the basis for the installation on the iPhone 7 Plus. The download of that backup took around an hour, and the apps followed later.

The most noticeable difference to the feel of the new device (apart from the sense from the glossy Jet Black finish) is the haptic feedback from the home button. Rather than the springiness of the older buttons as they were pressed, the Taptic engine gives the user a small jolt, making ot feel as if the whole phone is responding. Settings allow three levels and I felt happiest with the most powerful.

The haptic feedback is there in several of the apps and I tried a couple of games: shooting a canon gave me a slight kick; and this extends to other apps as well.

The change to the home button was for waterproofing. With a totally sealed button as well as the other buttons on the device, Apple has been able to claim IP67 dust and waterproofing levels which would keep the iPhone safe for 30 minutes at a depth of 1 metre, although, unlike the Apple Watch Series 2 this is not good enough for swimming.

Both iPhone 7 models have new camera installations and the output is considerably improved. Image Stabilisation was feature on the iPhone 6s Plus and this is now available on the 4.7" iPhone 7. On the iPhone 6s Plus this was invaluable when taking videos in moving cars or buses and also helped considerably in lower-light situations.

Unedited image (x1) from iPhone 7 Plus - straightened

The cameras have a larger aperture of 1.8 (before 2.2) and the 6-element lenses add to the improvements in image quality. A software feature of White Color Capture measures the range of colors and the result is enhanced vibrancy. The shutter speeds (25% faster than the iPhone 6s) also add to better colour handling. Low light images (an Achilles Heel of the iPhone for a long time) is improved with longer exposures: getting more light onto the sensors. Both phones now have improved True-tone flash with 4 LEDs: 2 white and 2 amber.

These improvements were obvious in a selection of photographs that I was shown in which images of the sky - with rich blues and white clouds - just popped. The same was so of other colours, like yellows and (especially) reds: sometimes hard to get right. Low light photographs too not only had an impressive sharpness, but colours were sharp and clear too. Once I had seen these samples, I was more keen than ever to take my own with the cameras.

Not only is the rear-facing camera improved, but the FaceTime cameras have been upped to 7 Mega Pixels giving better color captures. Apple is aware that the selfie is an important input for social interaction.

Images taken with iPhone 6s Plus (left) and iPhone 7 Plus

Zoomed images taken with iPhone 7 Plus - x2 (left) and x10

The iPhone 7 Plus has a new camera system with two cameras installed: wide-angle; and telephoto. Rather than manually switch between the two, there is integrated software so the operations of both cameras is seamless.

The use of both with the zooming facility allows for images not usually available on smartphones, and Apple is developing better depth of field software (currently in beta) that bring out the foreground while blurring the background. I usually need a DSlR camera and an 85mm lens for this; and now we will have this on an iPhone. The finished version is expected to be released by the end of the year.

The zooming is done by screen adjustments. A normal photograph has a bubble marked x1. When tapped this changes to x2 and the image zooms to twice the size. These are both optical effects. If that bubble is touched, it can be dragged and a dotted line in a semi-circle appears on screen. As the fingers move along the line, so the zoom changes up to x10: digital zoom.

Other forms of picture-taking also use the zoom:

• Video: 1-2 optical and 2-6 digital
• Time-lapse: 1-2 optical
• Panorama: 1-2 optical

That A10 Fusion processor is claimed to be 40% faster than the iPhone 6s with 60% better graphics performance. Comparing with the older iPhone 6, the iPhone 7 has twice the CPU performance and 3 times that for the GPU.

Battery life has improved too with the iPhone 7 life reported to be 2 hours better than the iPhone 6s, and the iPhone 7 Plus having 1 hour more than the iPhone 6s Plus.

Unedited image (x1) from iPhone 7 Plus - straightened

Graham K. Rogers teaches at the Faculty of Engineering, Mahidol University in Thailand. He wrote in the Bangkok Post, Database supplement on IT subjects. For the last seven years of Database he wrote a column on Apple and Macs. He is now continuing that in the Bangkok Post supplement, Life. He can be followed on Twitter (@extensions_th)