Along with Windows 10 Insiders Preview build 17755 for PC, Microsoft updated the "Your Phone" app to allow you to read and compose SMS messages directly from your PC. This is intended to be release with Windows 10 October 2018 Update (Redstone 5).
If you are a Windows Insider, you can now try it with the latest Windows 10 build and provide your early feedback to Microsoft.
Along with Windows 10 build 17730, Microsoft first previewed the "Your Phone" app. The first version of the app only includes integration of photos. Using this feature, if you have Android mobile, you can take photos using your mobile device and view it in "Your Phone" app. You can also drag the photo from the "Your Phone" app to your desktop or any other app and start editing it. This requires you to configure the app in both your mobile and PC.
Now with the latest update, you can now compose and read messages from your PC. At this moment, this is only supported when connected to Android mobiles. Microsoft not yet confirmed by when this feature will be available to the iPhone users.
So, if you are a Windows Insider (Fast Ring or Skip Ahead) and holding an Android device, checkout this and share your feedback. During the initial setup process, if you face any issues, here are few troubleshooting tips that you would like to follow.
If you don't know, Windows 10 October 2018 Update is the official name of next Windows 10 feature update and is scheduled to release globally in the month of October 2018.