Get notified when your boss emails
Tone down the number of email alerts you receive by using the new Notify Me feature in iOS 8. With it, you can set alerts for any email thread.
To enable thread notifications, swipe left from the message list > More > Notify Me.
For more on customizing the feature, check out this post.
Cut the clutter
Double-tapping the home button in iOS 8 not only shows you the app switcher, but also displays your "Favorite" and recent contacts.
To customize this feature -- or to disable it entirely -- follow these steps.
Find out what's killing your battery
Finally -- finally! -- there's a tool that shows you how much power your apps use. The tool organizes them in a list starting with the app (or setting) that demands the most.
Find out more about iOS 8's battery usage tool.
Use the camera's built-in tools
Apple knows how much its users like taking photos, so it included some really useful camera tools in iOS 8. You can now control exposure without affecting the focus, and even shoot timelapses.
Get to know all of iOS 8's camera features.
Add widgets to the notification center
Widgets give you at-a-glance information about any given app, and are a huge time-saver.
For example, instead of launching a sports app to check the score, you can view the status of the game by swiping down from the top of the screen to open the notification center.
Widgets can even be interactive. Find out how to add, remove, and customize your widgets.
One Apple ID for the whole family
With a short setup process, you can enable shared purchases, photos, locations, and calendars for the whole family.
The feature makes a lot of sense for people who want to share app purchases with other members of the family. No more having to purchase twice.
Find My iPhone -- even when your battery is dying
If you lose your phone as the battery is dying, Apple can now automatically save its location data, increasing the chances of finding your phone. In order to use it, you'll have to enable the option in your iCloud settings.
Bigger text for happier eyes
Adjusting the system-wide text size is easier than ever in iOS 8, since it's no longer buried in Accessibility settings.
Pick up where you left off
With Handoff, you can easily switch from your iOS device to your Mac, so you can continue whatever you were doing without interruption.
It works with Messages, Safari, Reminders, Contacts, Maps, Keynote, Pages, Numbers, and Calendar.
Want in? Check out our guide to using Handoff.
Hand-free Siri commands
Want to prompt Siri without holding the home button? There's a setting for that.
With the setting enabled, you can say "Hey Siri" and the personal assistant will start listening. There's just one catch -- your phone needs to be plugged in.
Ditch Apple's stock keyboard
Want to "swipe" instead of type, like Android users? Or, want to increase the size of the keys?
You can now do that by replacing the regular keyboard with third-party ones like Swype and Swiftkey.
Customize quick reply for Messages
In iOS 8, you can reply to messages without launching the app. A window pops up, you type your response, and you're done.
The way these "quick reply" notifications appear depends on your settings. Go to Settings > Notifications > Messages and choose between "Badge" or "Banner."
Your location, your privacy
In an effort to better protect your privacy, Apple now lets you decide when exactly apps can see your location.
Hidden tricks in the Mail app
From gestures to quickly adding new events, Apple's Mail app is packed with useful, understated features that could easily go unnoticed.
Accidentally closed a tab? Don't panic. In Safari, you can reopen closed tabs by creating a new tab, then selecting it from the list of recently closed tabs.
Check out three more Safari tips for iOS 8.
Hide App Store suggestions
Overall, the new App Store is awesome, but one feature that might annoy you is "Suggested Apps," which displays app suggestions based on your location.
They can feel a lot like ads, so if you'd like to get rid of them, here's how.
Siri types as you talk
The new, smarter Siri will now display your dictation as you speak.
Safer searching with Duck Duck Go
If you don't want your web searches to be tracked, change your default search engine to Duck Duck Go. You can do this by going to Settings > Safari.
A very minimal home screen
The jury's out on whether or not this was possible in iOS 7. If it was, it was a late-add feature.
In any case, it's worth knowing. Minimalist types can rest easy knowing that the entire home screen can be cleared out to display absolutely nothing. Just drag your current icons to another window.
Get the desktop version of a site
Oftentimes, mobile versions of websites omit important links and features. Any time you want to see the full desktop version of a site, tap the address bar, then drag your finger down to display the option.
Hide (or disable) text predictions
As you type, iOS 8 will suggest words in the bar across the top of the keyboard. Sometimes it's dead-on, and other times...not so much.
To temporarily hide tetx predictions, pull down from the bar. To show them, pull up from the top of the keyboard.
Otherwise, you can disable the feature entirely by going to Settings > General > Keyboard, and toggle "Predictive" off.
Touch ID everywhere
Touch ID can now be used in third-party apps (like Mint). Expect more developers to incorporate this feature as they issue updates.
Create your Medical ID
Should you ever be caught in a medical emergency, EMS workers can access your Medical ID without needing to unlock your phone. To set up your Medical ID, launch the Health app, and tap the last tab.
Share your location with friends
The Messages app is packed with fun and useful features, including one that lets you share your location on a one-time or ongoing basis.
Just hit "Details" and choose from the location-sharing options.
Check out our full guide to messaging on iOS 8.
Swipe to dismiss notifications
To quickly dismiss an alert from the notification center, swipe left over the alert and hit the "x."
Check times for sunrise and sunset
At the bottom of the 10-day forecast for any city, you can now view sunrise and sunset times, along with other, very specific weather information.
There's even a "pressure" measurement, if you're into that sort of thing.
Stay up-to-date on your favorite blogs
Safari can now act like an RSS reader, giving you a list of recent articles for any blog you subscribe to.
To subscribe to a blog, tap the bookmark icon, then the @ symbol, and hit the Subscribe option in the bottom-right corner.
Hide embarassing -- or inappropriate -- photos
Don't want friends seeing your selfies when they check out your photo gallery? Just tap and hold the photo you want to hide and choose "Hide."
Go grayscale
For an experience a little easier on the eyes -- or to prank your friends -- make your phone go grayscale. It's not yet clear if doing so saves battery life, but it can be a boon for tired eyes.
Want more?
For more tips, check out our complete guide to iOS 8.
Fixing the botched iOS 8.0.1 update
El app Health en iOS 8.