Unreal Engine 4.15 was released with significant gains in overall stability, enhancements to developer workflows, and improvements to runtime performance - including 79 improvements submitted by UE developers on Github.
The full list of new features is extensive, so here are a few of our favorites:
Nintendo Switch Support
Mobile Rendering Preview (OpenGL ES 3.1, Metal, Vulkan)
Preview high-end mobile features in the editor's viewport using improved Mobile Preview feature. This mode emulates the feature set available to iOS Metal, Android OpenGL ES 3.1, and Android Vulkan devices.
Physically Based Default Post-Processing Settings
Default tonemapper provides more film-like color tone and response.
Improved Texture Streaming
Optimized to reduce CPU usage, memory usage, and load times.
Cooking Blueprints to C++
Reduce Blueprint overhead.
UI Blur Rects
Blur other UI and the 3D scene.
Material Editor Reroute Nodes
Reroute nodes are now available to help simplify and better organized Material graphs. No impact on final instruction count of materials.
Sequencer Animation Blending
Now supports weighted blending between multiple animations for complex animation sequences. Any number of animations can be blended at any time.
Significantly improved support for reloading packages from disk on the fly. All in-editor source control operations are more stable, and a "Reload" option is now available to force asset reloads from disk.
HDR Display Output
UE4 can now output to High Dynamic Range displays taking advantage of higher contrast and wider color gamut displays.
Playstation(R) VR Aim Controller Support
UE4 games on PlayStation(R) VR are even more immersive with support from the PlayStation(R) VR Aim Controller.
For the full list of features, preview screenshots, videos, and the full release notes head over to the Unreal Engine Blog.