It's a new stable release of Construct 3! If you're updating from the last stable release r268, then this update includes changes from r269, r270, r271, r271.2, r272, r272.2, r273, r274 and r275. Highlights include:
• New support for sub-layers, helping organise long layer lists, efficiently processing effects on multiple layers, and making new kinds of effects possible
• New 3D effects like Fog and Depth Stripe (including support for third-party depth-based effects)
• Support for effects on the 3D shape object
• Audio tracks for timelines
• Loads of new examples! Check the new tag in the "More..." section of the Start Page
• Improved handling of the virtual keyboard on Android
• Support for web adverts with Mobile Advert plugin - see this forum thread for more details
• Lots more bug fixes, optimisations and improvements - see all the intervening release notes for full details.
We'll be starting a new beta release update cycle soon. If you'd like to help test it, try the beta release opt-in: choose Notify me about updates for beta releases in Settings. Please note due to staff time off around the holiday season, the next beta release cycle won't start until early January.