iOS 10 magnifier - good, but Apple could do better?

I've just added this piece about Magnifier to my notes for blind and partially sighted iOS users whom I have trained. I'd welcome comments.

There are many third-party apps that enable iPhones and iPads to be used as video magnifiers. With iOS 10 Apple has introduced a built-in magnifier feature which is essentially a modified version of the Camera app for people with sight loss. I have a few reservations about the controls, but once it is set up the way you like to use it, I think it will be a useful addition to the accessibility tools.

This is how to set up the magnifier:
The magnifier needs to be made available in the accessibility settings. Go to Settings/ General/ Accessibility/ Magnifier and turn on the Magnifier. There is also an Auto-Brightness switch which I have left turned off. You may like to experiment with Auto-Brightness later. Turning on the magnifier in settings makes it available through the accessibility shortcut, which is a rapid triple click of the circular Home button. This seems to be the only way to turn on the magnifier. Sadly, it doesn't seem to be built in to Siri yet. So, if you have difficulty performing a rapid triple click of the Home button, then the magnifier may not be available to you. For people who have difficulty with rapid Home button clicks, there is a Home setting in Settings/ Accessibility which offers click speeds of default, slow and slowest. The slow or slowest settings may make it easier for you to perform a triple click on the Home button.

There's one more possible complication in setting up the magnifier. If you already have something assigned to the accessibility shortcut, for example turning VoiceOver on and off, then the magnifier will be added to your accessibility shortcut options and a triple click of the Home button will bring up a box on screen asking you to select between VoiceOver and Magnifier. If you currently have VoiceOver turned on, then VoiceOver will speak the choices in the usual way and you can swipe to the magnifier and double tap. If VoiceOver is turned off, then, ironically, you may need to use Zoom to be able to read the choices you've been presented with. My personal preference is to remove VoiceOver from the accessibility shortcut so that a triple click of the Home button always brings up the magnifier straight away. VoiceOver can still be turned on and off using Siri. The settings for the accessibility shortcut are in Settings/ General/ Accessibility/ Accessibility Shortcut.

This is how to use the magnifier:
Triple click the Home button. So long as you have followed the advice above, this will launch the magnifier. The magnifier always seems to start as you last left it. Unlike apps, it can not be dismissed in the app switcher to restart it. On the whole, this is probably a good feature; once you have set the magnifier the way you like it, that is how it will stay. To use the magnifier, simply point the iPhone or iPad at your subject and pinch out with two fingers to magnify and back in to reduce the magnification. There is also a magnification slider on the screen which you may be able to see and use. The large circular button on the screen freezes the screen image so you can examine it without needing to hold the iPhone or iPad steady. You can also pinch to change the magnification of the frozen image. If the circular button is no longer on screen, touch the screen and the circular button and other controls will appear again. Touch the circular button to unfreeze the screen.

The small button at the bottom right of the screen brings up the full set of magnifier controls. Unfortunately these are quite small, so many users will also need to use Zoom to read the controls. Magnifier works well with VOiceOver so this may be a better option for users who are proficient with VoiceOver.

For these notes, I will assume that you are not using VOiceOver. The top control is a slider that lets you choose a filter. The choices are none, white/blue, yellow/blue, greyscale, yellow/black and red/black. This is similar to the filters on most video magnifiers. For many of us, none, that is, make no changes to the colours is probably best, but feel free to experiment.

Below the filters there are two sliders. The first is for brightness and the second is for contrast.

The button at bottom left inverts your currently selected filter. For example, if the current filter is none and you are looking at black print on a white page, touching the invert button will have you looking at white print on a black or grey page. The button at bottom right of the magnifier settings will take you back to the main magnifier screen.

There are two buttons at bottom left of the main magnifier screen on an iPhone and just one on an iPad.
On an iPhone, the buttons are "torch" and "focus lock". Torch turns on the flash to illuminate the subject and the focus lock button locks the focus. This can be useful when you're doing something like writing with a pen. You can lock the focus on the writing and ensure the device doesn't try to focus on the pen or your hand.

On the iPad, the torch button is absent.

And that is about all there is to say about the magnifier. It is a useful tool, but it is a pity that the controls are not larger and more accessible and that it can only be accessed through a triple click on the home button.