The Photos app contains more options to edit photos. The cropping feature now enables rotating images both clockwise and counter-clockwise. Furthermore, users can set the desired brightness and colors for photos. The Camera app now features a shot timer, which can be set to 3 or 10 seconds.
Notification Center is much improved in comparison to iOS 7 and 7.1. Users can now add and remove widgets in Notification Center with the "Edit" button. This also allows the rearrangement of notification widgets. From iOS 8 beta 3 onwards the "clear" button, used to clear notifications, is more visible.
In the Messages app, users can send audio and video messages by holding down the record button. In group conversations, users can add or remove someone from a thread, name a thread, share their location in a thread, view all attachments, and turn on Do Not Disturb to not receive notifications from a specific thread.
iOS 8 includes a new predictive typing feature called QuickType. It displays word selections above the keyboard as one types. The feature can be turned off in Settings, or hidden using a swipe gesture. Additionally, iOS 8 will allow users to install third-party keyboards. Many developers stated they would port their keyboards to iOS, including Minuum,Swype, SwiftKey, Fleksy and Adaptxt.
New to iOS 8, a user can add six others as family members. Family members can share purchased apps, music, and books using the same credit card. iOS 8 can also automatically set up photo streams for all family members. Calendars may be synced between all members. Kids can also send iTunes download requests for apps, music, movies, and more to their parents provided this service is set up correctly.
iCloud Drive is Apple's file hosting service for devices running iOS 8 or OS X Yosemite. This feature allows users to save photos, videos, documents (Keynote, Pages, and Numbers), and music, and other apps' data to iCloud. Users can start their work on one device and continue on another device. By default, users will get 5 gigabytes of storage for free, but this space will be expandable via subscription.
HealthKit is a service that allows developers to make software that integrates with the new Health application. This application allows users to track their steps, oxygen, sleep levels, and other health related data. Additionally, users can enter their medical history, so that the application can help serve them better. In a commercial for the iPhone 5S, the exercise song Chicken Fat is used to promote the new service.
Continuity allows users to share documents, e-mails, and websites over Wi-Fi to iOS 8 and OS X Yosemite devices. For example, when working on an email, Pages document, Keynote presentation, Numbers spreadsheet, viewing a location in Maps or browsing Safari on the Mac, on the lock screen of the iOS device it shows what app users are currently using on their Mac and will allow them to pick up where they left off in the app they were using on the Mac. This also works in the other direction. Continuity also allows users to reply to SMS messages and answer phone calls on their Mac or iPad if they own an iPhone. This feature is supported only by compatible Macs running OS X Yosemite, or by devices running iOS 8.
In iOS 8, Spotlight is integrated with a number of web services so that users can search using Wikipedia, Bing, or Google. Other services include: news, nearby places, suggested websites, movie showtimes, and content that is not already on the device from the iTunes Store.
In iOS 8, Apple integrated Wi-Fi calling. This service allows mobile phone calls over Wi-Fi. It is planned to be available for customers of T-Mobile in the US. According to Computerworld, Vodafone might also provide this service for its customers in Australia. Since beta 3, Wi-Fi Calling is available to T-Mobile customers in the US.
Siri now outputs what users say as they speak for more accuracy and has integrated Shazam support. Holding down the home button will activate Siri, and using the microphone, it will detect what song is playing. Also, saying "Hey, Siri" whenever the device is plugged into a power source will activate Siri if the feature is turned on. Purchasing content through Siri is now possible, and Siri now has support for 22 new languages.
Although iOS 8 has only been released in Beta form and is specifically designed for use by Apple Developers, it has been confirmed that non-developers are able to install the software on their devices. However, this is a dangerous process as Apple can detect an unauthorized install and de-activate the device. In addition, once the beta expires your device will be locked down. 
Time limits and countdown timer for Guided Access.
Background location notifications – popup asking to "continue to allow" apps accessing Location information while running in the background.
More Location Services options per app.
Camera added to Privacy settings.
HomeKit added to Privacy settings.
Health added to Privacy settings.
Search Photos by location and more.
Date, time and location information displayed.
"Recently Deleted" album.
Photos and videos can be hidden from Moments.
Hidden photos and videos get added to the "Hidden" album.
Separate Albums for Bursts, Slow-Mo's, and Time-Lapse Photos.
Auto optimise storage on device by removing local copies of pictures and videos option added.
Smart composition tools.
Play/Pause button next to the record button in Voice Memos.
App shortcuts on the Lock Screen based on your location.
iTunes Radio "buy" song button on Lock Screen.
iTunes Radio skips remaining displayed on Lock Screen.
New animation when opening apps from the Lock Screen.
Access to Medical ID from emergency dialer.
New "Slide to Unlock" text in certain languages.
QuickType – as one types, they see choices of words or phrases one would probably type next, based on their past conversations and writing style, using a more formal language for mail, and a casual one for Messages. The system also adjusts the system based on the person one converses with, and the region of the user (currently available in 14 countries).
QuickType can be hidden by swiping down.
QuickType can be toggled on or off from within the keyboard switcher.
Smiley icon for when emoji keyboard is the only alternate keyboard setup. Becomes a globe icon when multiple keyboards are set up.
Streaming voice recognition for Speech to Text.
Support for third-party keyboards.
iOS 6 keyboard no longer appears in apps that are not updated for iOS 7 or higher.
New keyboards (Indian, Tagalog, Irish Gaelic, and Slovenian).
Family Sharing – a service of sharing purchases from iTunes between up to 6 people.
All groups members must pay for family purchases with the same credit/debit card.
Ask To Buy – a parent can approve kids’ spending right from a parent’s device.
Coincides with iCloud Photo Library – automatically sets up a family photo stream where you can share photos, videos, and comments, and all the family photos are available from any device within the family.
Offers shared calendar and Reminders.
Family Sharing can automatically share the user's location with the family members, or keep their location hidden.
With the Find My iPhone app, family members can use their devices to locate one that’s lost and have it play a sound.
Apple IDs for kids under 13 are now possible due to Family Sharing.
Health app –shows a dashboard of all the fitness and health data of the user.
Shows the heart rate, calories burned, blood sugar, cholesterol, etc. of the user.
One can create an Emergency card with medicinal details, from within either the application or the lock screen.
Natively tracks steps taken and other movement activity within the Health app.
Export health data.
Continuity – iPhone, iPad, iPod Touch, and Mac communication
Handoff – start writing an email or surfing a website from one device, then carry-on the activity from another device. (Requires all devices are connected to the same iCloud account and requires Bluetooth LE, excluding iPad 2)
Answer a phone call, receive and send SMS/MMS from an iPhone on an iPad or a Mac. (Requires all devices run iOS 8/OS X 10.10 Yosemite, and are connected to the same Wi-Fi network or to the device's hotspot).
Intelligent hotspot – intelligently discover when an iPhone is nearby and automatically list the device under Wi-Fi networks in Settings.
Every app installed now has its own settings panel, regardless of whether the app specifies its settings to appear in the Settings app (e.g. Notifications, Privacy, Background App Refresh, and Cellular Data usage).
Battery usage info per app in Settings.
A new "Allow Notifications" setting for each app.
"Raise to Listen" setting for Messages.
New Handoff and Suggested Apps under General.
Wallpapers and Brightness has been split into two separate menus:
"Display and Brightness": Brightness settings were moved here and Text Size and Bold Text from General and Accessibility is now included as well.
"Wallpapers" is now standalone.
EU options for roaming.
Wi-Fi network scanning will use random, locally administered MAC addresses, to aid users' security/privacy concerns.