1/ Triple-click for accessibility shortcuts — iOS has many accessibility features available in Settings, but there’s a faster way to access them. Tap Settings > General > Accessibility, then scroll all the way down and tap Accessibility Shortcut. Next go ahead and tap the accessibility features you use the most—you can tap one, all, or just a few of them. Features include VoiceOver (which will read aloud aloud anything on the screen), Zoom (lets you zoom in or out on the display by pinching the screen), Grayscale (renders all the colors on the display in shades of grey) and Invert Colors (reverses all the colours on the screen, making for a de facto ‘dark mode’, for example, while browsing in Safari. There’s also Assistive Touch and Switch Control, a pair of features for those who need help tapping and swiping a touchscreen.
Now when you go back to the home screen and triple-click the Home button, if you selected more than one accessibility shortcut, a pop-up listing all your selected shortcuts will appear; just tap the one you want.
If you only selected one shortcut, that accessibility feature will immediately switch on. Triple-click the Home button again to turn off the accessibility option or to return to the shortcut menu.
2/ Change the double-click speed — If you’re having a tough time double-clicking your iPhone or iPad’s Home button fast enough, why don’t you slow things down?
Tap Settings>General>Accessibility>Home Button, then pick a speed: Default is the fastest, but you can also choose Slow, or Slowest. The three options blink as you tap them, giving you an idea of how fast you’ll have to double-click.
3/ Turn off Reachability — Older iPhone models look puny now, compared to the bigger iPhone 6 and 6 Plus versions, but the smaller 3.5- and 4-inch iPhone screens have one advantage over their bigger brothers: you can access the entire thing with your thumb while holding the device in one hand. So iOS has a Reachability feature making the screen contents all reachable, and this can can be summoned by accident. Reachability moves the entire screen down to about the midpoint of the display, making it easier to reach the top of the interface with your thumb. You can activate Reachability by double-tapping, but not pressing, the Home button.
Tap Settings>General>Accessibility, then switch off the Reachability setting you don’t want it activating by mistake.
4/ Summon Siri from the lock screen (or not) — Helpful though she can be, Siri has a bad habit of appearing on my iPhone screen when I need her the least. Maybe something’s up with the Home button on my iPhone 6, but Siri frequently pops up on my screen when I’m unlocking my iPhone, or when I’m trying to double-click.
You can’t change the default method of summoning Siri—pressing and holding the Home key – but you can keep it from appearing on your iPhone or iPad’s lock screen. Tap Settings>Touch ID & Passcode, then switch off the Siri option under the Allow Access When Locked setting. [These tips came from Macworld.]
5/ Easily remove a colour cast from an image snapped on your iPhone or iPad — There’s an editing tool in iOS 9+ that lets you remove a colour cast (when white areas don’t look white, for example) in a couple of seconds. Find the photo you’d like to change, and tap the Edit button.
When you see the tools appear, touch the Adjust button which brings up the tools for adjusting Light, Color, and B&W.
Tap the arrow next to any of those sections, and you’ll see more advanced options; to get to Cast, tap the arrow beside ‘Color.’
Then tap Cast to make changes, and you’ll see a little bar you can move back and forth. Dragging it to the right will make the image cooler (as below), and dragging it to the left will make it warmer.
Remember that edits to your pictures in Photos (on Mac and in iOS) are nondestructive, meaning that if you click on Edit again after you’ve made changes, you always have the option to revert to your original.