Here is a massive change log compiled by nokiapoweruser.com
System / Settings UI Changes :
New Tile Re-sizing animation with Fade-in/out effect.
Icons for individual settings pages: All pages in the Settings app now have individual icons associated with them. These individual icons will also be shown when you pin a settings page to Start. And a dropdown flyout with page suggestions that will appear as you type into the Settings search box. These changes are designed to make it easier to find the settings you are looking for.
Glance screen settings have moved: As part of our work to make settings more discoverable and user friendly, we’ve simplified the Glance settings options and moved the page out of the Extras section in the Settings app. These settings can now be found via Settings > Personalization > Glance screen. With this change, Glance settings no longer need to be downloaded or updated from the Store.
Camera button on the Lock screen: When your phone is locked, the back button on the navigation bar is now replaced with a camera button. Press and hold this button to launch the Camera app from the Lock screen.
Media controls show on top of the Lock screen: While you are listening to music, you will now be able to control the music you are listening to right from the Lock screen! If you turn on your phone’s screen, the media controls will now be shown embedded right on top of the Lock screen.
Navigation bar settings page and vibration setting: We created a page for the navigation bar at Settings > Personalization > Navigation bar. You can now use this page to configure preferences for vibration and double tap the navigation bar to turn off the screen.
Device Encryption has moved under “Update & Security” in one more unreported change.
There is new “Your Info” section under Accounts Settings
Action Center / Notification UI & other Changes:
Visual changes to Action Center: Individual app notifications in Action Center no longer show the app icon repeated for each notification and will only be seen in the header that groups together all the notifications specific for that app. This change allows for more space in Action Center to show more content.
Visual changes to Notifications: We’re making Action Center richer with support for notifications with more flexible layouts similar to the richness of Live Tiles. Notifications with images will now display larger than they did previously. Notifications can have “hero image” for content that is an even bigger image size to make content in notifications pop even more.
Cortana notifications in Action Center: We have also added new insights from Cortana to ensure you are not missing anything important, such as a meeting conflict or anything she needs to remind you about.
Notification prioritization in Action Center: You can manage the notification settings for individual apps by going to Settings > System > Notifications & actions and prioritize which app notifications are more important to you. You can prioritize its notifications to be in one of 3 levels: Normal, High, or Top. You can also adjust how many notifications are visible per app. The default is now 3 per app. If an app has more than 3 notifications, just click or tap to expand and see all notifications for that app. This feature is also available on PC starting with Build 14316.
Customize your Quick Actions in Action Center: You can add, remove and re-arrange the Quick Actions that show up in Action Center. To customize your Quick Actions, just go to the Settings > System > Notifications & actions. In this settings page, you will see a replica of your Quick Actions as it appears in Action Center, and with a simple press and hold you can move the Quick Actions to the place where you want them to be. Then to add or remove a Quick Action, there is a link below the grid that will allow you to turn on or off the available Quick Actions.
Notifications can be disabled from appearing in Action Center only, but still can show banners and other notifications
if you long press on notifications & group name of notifications in Action Center you get a context sensitive menu with useful options like,
Make this app high-priority
Turn-off notifications from particular app
Go to notifications settings directly
App update notifications are back in Action Center now
Phone related Changes:
Audio Routing options are new and useful. You can choose between Automatic, Bluetooth device and Phone Speaker when you make or receive a call. Also you can toggle on the option of “while making a call, turn on the speaker when I move my phone away from my ear”.
Missed call and voicemail waiting indicators to the tabs inside the Phone app. Once you navigate to a tab with a missed call or voicemail – the indicator goes away.
Advanced Settings allows one to get call transfer button in the call UI
Visual Voicemail for dual-SIM devices such as dual-SIM Lumia 950 XL
Change in Screenshot / Camera sounds:
If you check you will hear new Screenshot capture and Camera sounds.
Now you can have up to 16 Apps cards open in Multitasking UI on devices with 2 GB and higher RAM
Microsoft has revealed Notification Mirroring as the way to sync notifications on connected Windows 10 PC and Mobile devices. Users would be even able to opt out of notification mirroring for particular apps. The settings to opt out of the notifications mirroring will be listed in Cortana’s Notebook. Go to Cortana Settings–>Edit Sync Settings.
Cortana will now also surface your phone notifications and critical alerts, including low Battery alerts, messages from messaging services, SMS or social media as well as missed calls from any Windows 10 phone or Android device to your PC, so you never miss a beat while staying focused on your PC.
Send a photo from your phone to PC: If you need to quickly transfer a photo from your phone to your PC wirelessly – just ask Cortana “send this photo to my PC” and see what happens. This feature is currently exclusive to Windows 10 phones.
New listening animation: When you tap the mic icon in Cortana, there is a new animation that shows Cortana is listening to you as you speak.
With this build, we are enabling Cortana for the Spanish (Mexico), Portuguese (Brazil) and French (Canada) languages for Mobile (available previously in PC builds).
You can change the Cortana language right in Cortana Home all thanks to a new option provided in its Settings. Cortana keeps working on your device even if you change its language to available options English UK, US, Australia or Canada.
More ways to create Cortana Reminders: We are making it easier and quicker to set a reminder in Cortana with 2 new exciting ways to create reminders. You can now create a Photo Reminder by taking a picture of something you want to be reminded about, like that beer you just tried and want to pick up next time you’re at the store. You can also now set reminders on content from UWP apps that utilize the share contract in Windows, like Microsoft Edge and the News app, so you don’t forget to read that article your friend sent you. You can share an article from the News app to Cortana and have her remind you to read it at a later time. This even works with photos from your collection in the Photos app! Give it a try.
Search for music easier in Cortana: We have made it easier to invoke music search in Cortana by adding a music search icon to the top right of Cortana. You can now open Cortana and tap on the music search icon to have Cortana listen and search for the song that’s playing.
Here is one of the unreported features which allows one to delete test messages by simply swiping left. Once you have deleted the messages you are also presented with the option of “undo” you action.
Not only swipe to delete has been added to messaging with Build 14327, there is one more feature that has made a comeback. You an again tap left to any of the messages and multi-select or select all of them. This was again a much used feature that went missing on Windows 10 Mobile.
Swipe navigation in Microsoft Edge: Since the release of Windows 10 Mobile, our top feedback request for Microsoft Edge has been asking for the return of the swipe gesture to navigate back and forward. With this build, you can now swipe from anywhere on the page to get back to your previous page.
Microsoft Edge has “Account Settings” and “Device Sync settings”shortcuts. The purpose seem to be easy accessibility of these settings from Microsoft Edge itself.
Better tab behavior: Microsoft Edge keeps your tabs under control when you use it with apps on your phone. If you tap on a link in an app that opens a new tab in Microsoft Edge, pressing the back button when you’re done will close that tab, then take you back to the app. Your tabs list stays lean and relevant, by smartly closing tabs you’re done with.
Word Flow now works in the address bar in Microsoft Edge on your phone: For fans of Word Flow, we heard your feedback, and we have re-enabled the ability to use shape writing in the address bar in Microsoft Edge on your phone!
Open InPrivate tabs more easily in Microsoft Edge on your phone: We take the need for private browsing seriously, and InPrivate has been a feature of Microsoft Edge in Windows 10 Mobile from day one. However, we received feedback from Windows Insiders that the InPrivate feature was either hard to find or missing on their phones. As a result, we’ve moved the button to create a new InPrivate tab to appear right next to the new tab button. The next time you need a private tab in Microsoft Edge, you’ll find it right in your tabs view. Try it out on your phone and let us know what you think.
Improved Download Prompts in Microsoft Edge: Microsoft Edge will now show a prompt when you start a download, allowing you to cancel unwanted downloads.
Software, OS Update & Restart changes:
Insider Preview Ring Selector has drop-down selection of ring instead of slider. Windows Insider App no more required. You need to go to Settings–>Update & Security—>Windows Insider Program to check this.
Updated Windows Update Settings: You can now also set the time in which you are most active on your phone just like on your PC by adjusting active hours under Settings > Update & security > Windows Update. Windows Update will avoid automatically installing updates during your active hours on your device.
Wi-Fi / Mobile Data Changes:
Wi-Fi Hotspot 2.0 feature is here now as can be seen in the first screenshot. You need to go to Settings–>Network & Wireless—>Wi-Fi—>Manage.
Insider Preview Ring selector has also landed and it presents similar slider to change rings, as seen in Windows 10 PC builds.
New only 4G or 3G option apart from existing 3G only option
Battery Saver Changes:
Updated Battery Settings and Battery Saving Experience: Just like what was seen in last week’s PC build, there is now a single entry point for all battery related settings in the Settings app – including Battery Saver. This also includes the updated the Detailed Battery Use page so you can now manage the per-app background settings inline without going to a second page.
You can also adjust the percentage in which Battery Saver turns on (which is at 20% by default) – something we had with Windows Phone 8.1 that Insiders wanted to see us re-implement as we merged Battery Sense into the Settings app for both PC and mobile.
New option of “Managed by Windows” to handle apps running in background
Typing & Keyboard Changes:
Updated emoji. This build brings our new emoji to your phone. As part of this work, the emoji section of the keyboard has been slightly reorganized to better align with the newly available emoji. It’s now arranged as follows: Favorites, Smileys and Animals, People, Celebrations and Objects, Food and Plants, Transportation and Places, Symbols, and ASCII emoticons.
Better copy/paste: We’ve made a couple of improvements to copy and paste on the phone. When you are typing into an edit box on a web page, you will now be able to use the paste button above the keyboard. Also, if you select text on a web page the copy button will appear immediately near the selection.
Movable Keyboard and one-handed keyboard mode now available on more 5-inch devices like Lumia 640 and Lumia 830
Major Apps Revamps:
Skype UWP Previw app: Microsoft removed Messaging-Skype integration in favour of the new Skype UWP Preview app.
All new revamped design and UI
Create and send group messages, as well as make group audio calls
Ability to make group video calls. You can have up to 25 friends and family come together on a free group video call, talk face-to-face with a 1:1 call, message your friends in an instant to share photos, emoticons and Mojis to liven up your conversation.
You can also quickly reply to Skype messages—no need to open Skype.
PSTN Out/Skype Out
Connectivity and Status awareness, Troubleshooter, and Offline Mode
Outgoing message status
Updated Maps app: This build includes a updated Maps app for Windows 10 that brings a more lightweight, scalable, and consistent UI as well as underlying architecture improvements and new features for you to try!
One-tap access to search and directions from anywhere, even on your phone. This is great especially for one-handed use.
You can view multiple searches and directions at the same time, on the same map as they are layered on top of each other and you can use tabs or the map to switch between them.
You can now minimize search results, directions, and location info to enjoy more of the map, while keeping them in easy reach.
You can see labels for your search results directly on the map. No more numbers to match between the map and the list.
Cortana will give you turn-by-turn directions (if Cortana is enabled).
We have improved the logic for nearby searches so you should see better (closer) results.
We have added the ability to search for your favorite city in the 3D cities list so no more scrolling forever to get to the city you want.
You can now access your favorites offline and add notes to them.
We have updated the turn-by-turn design to improve glanceability and landscape layout.
Updated Alarms & Clock app: We have pushed out an update to the Alarm & Clock app that introduces a new inline time picker and improved design for creating and editing alarms and timers
Updates to Outlook Mail & Calendar: Yesterday, we released an update to the Outlook Mail & Calendar apps that introduces some new features and improvements.
In Outlook Mail, you can turn off the message preview text in the message list (Settings > Reading > Conversation and turning “Show preview text” off).
You can also quickly get rid of junk email in your inbox by pressing down on a message to bring up the context menu and choosing ‘Move to Junk’.
In Outlook Calendar, you can now let others know “I’ll be late” directly from meeting notifications.
Send email from Outlook.com aliases
Open & save Calendar .ics attachments in email
See multiple upcoming events on the wide Calendar live tile
Drag and drop calendar events to reschedule them (PC only)
Print Month view in Calendar
Use Mail and Calendar on HoloLens
Update to the People app that brings back the history feature. For a given contact you communicate with, you can view the interaction, whether by today, yesterday, last week etc. Right now, your Skype messages won’t show up in history yet but we’re working on enabling this in a future update. Also – we’re tracking a bug in which opening an email item in history might not take you to that specific email.
Update to Store app brings redesigned UI and some cool features including information about when the app was updated last on your devices. It also makes updates apps accessible from Downloads & Updates Page. Everything including individual apps page, Store Home and even Downloads progress bar and UI gets revamped.
Update to Groove app brings Your Groove, the place for music that is centered around you, what you like, and your listening habits. This is where you’ll not only find your recently played items, but also brand new automatically curated recommended playlists built just for your taste. They update often to always give you fresh recommendations, but you can save a copy any time to edit, download or just save to listen to later. Some design improvements to make Your Groove and Explore more colorful and vibrant.
Feedback Hub improvements:
Introducing Feedback Hub: The Feedback Hub carries over all of the best things from the previous two apps plus a few new things. When you open Feedback Hub for the first time, you will see a search box at the top so you can quickly find and upvote feedback items from other Insiders or submit new feedback. You will also notice that Announcements and Quests show up together in a single feed under “What’s new”. When you submit new feedback to us, we have added a new description field so you can explain in more detail the feedback you are sending to us.
We’ve heard from you that it can sometimes be hard to find which category your feedback belongs in. Now when you create new feedback, the Feedback Hub will suggest categories and subcategories based on the title and description you entered. If you see a suggestion that looks right, just click it to fill in the menus and get your feedback to the right engineers quickly.
Commenting in the Feedback Hub. Just like on PC, you also have the ability to comment on feedback inside the Feedback Hub on your phone in addition to the responses from our engineering team you have seen in the app already (we call these “sticky comments”). So in addition to up-voting on feedback, you can now comment on feedback too.
Share Wi-Fi networks with your contacts removed: Just like we noted for Build 14342 for PC, we have removed the Wi-Fi Sense feature that allows you to share Wi-Fi networks with your contacts and to be automatically connected to networks shared by your contacts. The engineering effort to keep this working great, combined with low demand for the feature made it not worthwhile to keep investing in it. Wi-Fi Sense, if enabled, will continue to get you connected to open Wi-Fi hotspots that it knows about through crowdsourcing.
Removed Messaging-Skype Integration from the messaging app.
Kid’s Corner gets depreciated
Native FM Radio App gets removed
“Messaging everywhere” feature in Windows 10 that allows you to send and receive text messages from your phone directly from your Windows 10 PC’s.
USB Ethernet Support with Continuum (Mobile). Continuum-capable phones now include support for most USB Ethernet adapters. If you connect a USB Ethernet adapter your Lumia 950 or Lumia 950 XL via the Microsoft Display Dock for example – you will have network connectivity through an attached Ethernet cable. A few notes on this feature:
You may see an error message the first time you connect. There is nothing wrong with your adapter, and the message will be eliminated in a future update.
Not all adapters are supported yet – more will be added in a future update.
In this update, you will not see a visual indicator that you are connected, so if you want to double-check that it’s working you can turn off Wi-Fi and cellular data.
Windows 10 Mobile supports proxy configuration for Wi-Fi and VPN connections. Proxy support for LAN connections will be available in a future update.