Start.Provides resizable small, medium, and large Live Tiles so you can customize your Start experience in new ways.

Accent colors. Expands the number of available accent colors to 20.

Lock screen. Improves the lock screen experience with accidental wipe protection features and the Bing image of the day wallpaper.

Marketplace and Xbox. Expands Windows Phone Marketplace and Xbox support to new countries and regions.

Fonts. Enhances the Chinese font and improves the appearance of Arabic and other languages.

Live Tiles. Fixes performance issues from a previous update.

Other improvements. Includes many other improvements to Windows Phone.

*Windows Phone 7.8 is the official product name we use to describe this release. However, due to a quirk of software development, the actual OS version is identified as 7.10.8862.144. You'll see both of these names on your phone in Settings > About > More info.

Messaging.Adds new messaging capabilities to your phone. You can now attach multiple pictures, videos, audio notes, and ringtones to text messages.

Other quality improvements. Includes many other improvements to Windows Phone.

On-screen keyboard.Fixes an issue to prevent the keyboard from disappearing during typing.

Email. Fixes a Google mail syncing issue.

Location. Fixes a location access issue. With this fix, the Me feature in the People Hub sends anonymous information about nearby Wi-Fi access points and cell towers to Microsoft only if you agree to allow the Check In function to access and use location information.

Security. Revokes digital certificates from DigiCert Sdn Bhd to address an encryption issue.

Email threads. Fixes an email issue related to Microsoft Exchange Server 2003. With this fix, when you reply to or forward a message, the original message is now included in your response.

Voicemail. Fixes a voicemail notification display issue that occurs on some European and Asian networks under certain conditions.

Email threads.Fixes an email issue related to Microsoft Exchange Server 2003. With this fix, when you reply to or forward a message, the original message is now included in your response.

Voicemail. Fixes a voicemail notification display issue that occurs on some European and Asian networks under certain conditions.

Hundreds of new and improved features.Based on your feedback, we've scoured Windows Phone from top to bottom looking for ways to make it easier for you to connect and share with friends, discover and use smarter apps, and tap the power of the web.

*Windows Phone 7.5 is the official product name we use to describe this release. However, due to a quirk of software development, the actual OS version is identified as 7.10.7720

Fix for fraudulent third-party digital certificates.This update includes a critical fix to an industry-wide issue with nine untrusted digital certificates that were issued by one root certificate authority. These third-party digital certificates are used to access popular websites and email portals.

Although this is not a Microsoft security vulnerability, these untrusted certificates may be used to spoof content, perform phishing attacks, or perform man-in-the-middle attacks against all web browser users. This update moves the affected certificates to the "Untrusted Publishers" certificate store on Windows Phone, which helps ensure that these fraudulent certificates are not inadvertently used.

Copy & paste.Tap a word and drag the arrows to copy and paste it on your phone. You can copy text from emails, text messages, web pages, and Office Mobile documents, and paste it anywhere you can type.

Faster apps and games. Nobody likes to wait. That's why we've whittled down the time it takes for apps and games to start up and resume. It's all part of our focus on getting you to the things you love, easier and faster.

Better Marketplace search. We've streamlined Marketplace search to make it easier to find specific apps, games, or music. Press the Search button in the Apps or Games section of Marketplace and you'll see only apps or games in the results. Press Search in the Music section of Marketplace to search just the music catalog.

Other Marketplace improvements. We've improved the stability of Marketplace while you download apps. We've also improved the experience of downloading apps larger than 20 megabytes, upgrading from trial apps to paid apps, sharing links to apps via email, sorting Xbox LIVE games by release date, and creating an Xbox LIVE account from within the Games Hub.

Wi-Fi improvements. We now display your phone's Media Access Control (MAC) address in Settings. (You might need this info if you try to connect to a Wi-Fi network that uses MAC address filtering. To learn more, see Connect to a Wi-Fi network.) We've also removed the limit on the number of Wi-Fi profiles that you can store and reduced the time it takes to start your phone if you've stored lots of Wi-Fi profiles.

Outlook improvements. We've improved the experience of viewing iPhone photo attachments you receive from a non-Exchange-based email account (such as a Google Mail, Hotmail, or Yahoo! Mail account), using the Global Address List (GAL) when connecting to Exchange Server 2003 using Exchange ActiveSync, and working with email display names that contain brackets (for example, "David Alexander [Contoso]").

Facebook integration. We've improved the experience of syncing Facebook accounts.

Camera improvements. We've improved the stability of switching between camera and video modes.

Audio improvements. We've improved the experience of using a Bluetooth headset to make calls when you're playing music or videos.

Other performance improvements. This update also includes software from several phone manufacturers that improves the performance of specific models. Naturally, if you don't have one of the affected models, we won't install this portion of the update on your phone.

*New phones with OS version 7.0.7389.0 include all of the features and improvements that are included in OS version 7.0.7390.0.

Update process improvements.This behind-the-scenes update improves the update process itself.