A-Frame web framework for Virtual Reality.

As originators of WebVR, the Mozilla VR team developed A-Frame as a web framework for building virtual reality (VR) experiences.
The core of framework provides an declarative, extensible, and composable structure to three.js.
You can find some example with this framework here.
The blog of the development team and users come with useful articles.
A-Frame supports most VR headsets:

• Vive
• Rift
• Daydream
• GearVR
• Cardboard
• ... and can even be used for augmented reality

The framework come with aframe inspector the online tool for visual tool for inspecting and tweaking scenes.
The Sonar Systems youtube channel come with some video tutorials about A-Frame VR framework:

The Visual Components software.

Is a complex software application with many tools for engineers  and not just for them.
The team development tells us:
There are four main applications for the Visual Components software: an engineering tool, a sales tool, a robot programming tool and a platform for building your own simulation solution.
The parts of this project come with this issues:

• Layout Configuration 
• CAD Compatibility 
• Project Ready Deliverables 
• Simple Robotics 
• Component Modeling 
• Advanced Robotics 

With Python API, which is available in all Visual Components 4.0 products we have a good platform for teaching, automating and post-processing robot programs.
For training , courses are collections of lessons you need to visit this link.
See the video from official youtube channel:

You can download this application from here.

The Game Jolt platform for games.

Discover the largest community for indie games and the people who make and play them.
The Game Jolt (GJ) is a hosting service for freeware and commercial video games - most Indie games.
Started in 2002 the goal of Game Jolt has always been to grow indie gaming.
You need to sign in into gamejolt.com.
Then gain experience and level up to achieve trophies and get onto scoreboards!
If you are you a developer then you can add your free or commercial game to the site.

The new Krita 4.0.0 pre-alpha.

The Krita team comes with unique ways for pre-alpha versions.
The new Krita 4.0.0 is under development , but you can test it.
You can test the krita-4.0.0-prealpha.1-x64 version from official website and read the full article of this pre-alpha version.
This is the only demo video found on the web with version 4.0.0 created by eugening .

Principle - the design tool for iOS.

This application is a Macintosh-based UX prototyping tool designed to design animated and interactive user interfaces.
You can choose a device preset or enter a custom Art board size to design for your favorite platform and then with few moves make your interactions and animations design.
You can find many video tutorials on youtube.
Compatibility: Requires iOS 9.0 or later. Compatible with iPhone, iPad, and iPod touch.
Let's see one example from Principle Repo youtube channel:

Causality - another game for all operating systems.

Causality is a puzzle game about manipulating time, changing the sequence of events and altering the outcome of each level.
You need to help a group of stranded astronauts find a route to safety.
It is logical and not very hard. Can be found  here for Windows, Mac OS X SteamOS and Linux (Ubuntu 12.04+, SteamOS).
With a simple and beautiful graphics it can be played on smaller screen phones.
If you want the Android version then try this link.