The Photos app contains more options to edit your pictures. The cropping feature now enables you to turn the image clockwise and anti-clockwise. Furthermore, you can set the desired brightness and colors for your pictures. The Camera app features a shot timer, which can be set to 3 or 10 seconds. Additionally, the Camera app now allows for the capture of timelapse.
Notification Center of iOS 8 is much improved in comparison with iOS 7 and 7.1. Now you can add and remove widgets in Notification Center with the option of "Edit". Moreover, you can rearrange notification widgets. Now in iOS 8 beta 3 the "clear" button is more visible, and this clear button is used to clear notifications from the Notification Center.
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 has the same design as iOS 7, however, there are a few minor changes such as added transparency and faster animation effects. The multitasking screen now shows a list of recently called and favorited contacts.
iOS 8 includes a new predictive typing feature called QuickType. It displays word selections above the keyboard as you type. The feature can be turned off in Settings, or hidden using a swipe gesture. In addition, iOS 8 will allow users to install third-party keyboards. Many developers stated they would port their keyboards to iOS. Some of these include 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. The calendar can also sync 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 iCloud'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 on iCloud. Users can start their work on one device and continue on another device. By default, users will get 5 GB 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 & OS X Yosemite devices. For example, when you're working on a email, Pages document, Keynote presentation, Numbers spreadsheet, viewing a location in Maps, or if you're browsing Safari on your Mac, on the lock screen (iPhone or iPad), it shows you what app you're currently using on your Mac and will allow you to pick up right where you left off in that app you were currently using on your 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.
In iOS 8, Siri now outputs what you say as you speak for more accuracy and now has integrated Shazam support. To use Shazam support just open up Siri and wait for the song to be recognized. Also, saying "Hey, Siri" whenever the device is plugged into a power source will make Siri activate if the feature is turned on. Purchasing content through Siri is now possible, and now Siri has learned 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.
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.
"Home Data" for HomeKit 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.
Smart composition tools.
Play/Pause button next to the record button in Voice Memos.
Status bar is no longer enlarged on Lock Screen.
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.
Smiley icon for when emoji keyboard is the only alternate keyboard setup. Becomes a globe icon when multiple keyboards are set up.
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).
Streaming voice recognition for Speech to Text.
Supports third-party keyboards.
iOS 8 offers a swipe-based keyboard built in.
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.
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.
Shutter Mode (timer can be set to 3 or 10 seconds).
Camera added to Privacy 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).
More location services options per app.
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 is now Display and Brightness, Wallpapers is now standalone and Text Size and Bold Text from General and Accessibility is integrated into Display and Brightness
Wi-Fi network scanning will use random, locally administered MAC addresses, to aid users' security/privacy concerns.