A Quick Guide to Apple's iOS 8 and OS X Yosemite The new operating systems build upon their predecessors with deeper integration and sharing, and compatibility.

Today in San Francisco, Apple's World Wide Developers Conference was all about the company's upcoming software: iOS 8 for mobile and OS X Yosemite for PCs.

Both platforms have been improved to work more seamlessly, through the cloud, in order to make virtually all media available across all of a users' devices. Here's what you'll want to know about each, plus some important details for iOS developers.

OS X Yosemite: Apple has further tweaked the OS X motif to mirror the redesign introduced with iOS 7 with new, flatter icons and subtle color adjustments based on desktop image or windows behind it.

Users accustomed to Mavericks or Mountain Lion should be comfortable with Yosemite which includes new features such as the ability to search across contacts, documents, the web and calendar events from Spotlight -- which appears to also use geolocation to bring users relevant local information.

Apple's answer to Dropbox and Google Drive is iCloud Drive. It allows users to access all documents across devices from within the finder. With it comes MailDrop, a new feature that will allow users to send larger files that recipients might normally be able to handle by creating a secure link and storing it in the cloud, instead of bouncing the email back to the sender.

Related: What's That Song? Apple's iOS 8 May Be Able to Tell You.

On Yosemite, AirDrop will work between iOS and Mac with a new feature called Handoff. A new lock screen on the iPad lets users continue work they were doing on a PC on a mobile device simply by swiping. Users will also be able to setup hotspots on their phone from their computer.

Syncing an iPhone to a Mac will also allow users to answer text messages and even phone calls from their computer, using their Mac as a speakerphone. The feature also lets users make calls from a computer, even if their iPhone is in another room.

iOS 8: Apple's new mobile operating system will build upon iOS 7 in terms of feel and functionality but with some new features. In iOS 8, users will be able to reply directly to a message or comment or Like something on Facebook straight from the notification center or the lock screen and doubletap the home button to see recent contacts in the task switcher. Other upgrades include a new tab view in Safari for iPad and new gestures for organization in the Mail app.

Group messaging now allows users to name threads or remove people from the conversation. Messages will also include "Do not disturb" and "leave thread" features.

Messages will also allow users to record audio or video by tapping on the text box. It also includes a Snapchat-like self-destruct feature.

Spotlight for iOS, a tool that OS X has had for a while, lets users search for apps, points of interest, news, songs the web and iTunes. It's like Siri but without a voice.

Siri itself has been updated to make purchases from the App Store and recognize songs via Shazam.

Apple also seems to be updating its predictive text feature with QuickType, which "supports predictive suggestions" by guessing the word a user is trying to type and learning from their typing habits.

Related: Should You Buy an iPhone 5S Now or Wait For the iPhone 6?

With iOS 8 is the introduction of Healthkit, a centralized place to see health info that will allow healthcare providers to send and receive data on patient devices.

Also new is HomeKit for home automation. Apple is partnering with home appliance companies to integrate locks, lights, cameras, doors, thermostats, plugs and switches into the iOS environment. The new automated controls will feature secure pairing, control for individual devices, allow grouping of devices for families and include Siri integration.

New family sharing features allows families to automatically share photos, calendars and reminders and their locations. Families can also share purchases; for instance if a child wants to purchase an app on his phone, he can send a request to buy the app through the App Store and permission can be approved from an adult's device.

iOS 8 will also support Extensibility, the ability for apps to offer services to other apps. For instance users could use their photo filters from VSCO inside of the native photos app. The new iOS will also support widgets for the notification center and inside of Safari, similar to extension in Chrome.

Apple is also allowing users to import third-party keyboards and opening Touch ID to developers.

Developers: Apple is introducing a new programming language called Swift that can co-exist with C and Objective-C but allows developers to build and run their code immediately.

Game developers in particular will welcome the new Metal graphics booster and SpriteKit and SceneKit for developing casual games.

iOS 8 and Yosemite are both available to developers today and will be released to the public for free this fall.

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