About one year ago I found a cool piece of software called Unity. In Unity you can make games, I believe the game Angry Pigs was made in Unity, and you can also make simulations, like my own Tesla Motors Simulator. The good thing with Unity is that you can focus on building your product instead of first focusing on building a game engine and then your product. This will obviously speed up the process and I don't even know if it is realistic to learn both in a short amount of time. Earlier I considered this cheating (to not build everything yourself), but hey, even Minecraft used libraries built by other developers and they turned out fine.
But back to Unity. There are basically 2 competing game engines: Unreal and Unity. A few days ago, Unreal revealed that their engine would be free to use, and yesterday Unity revealed that their new engine, Unity 5, would also be free to use. Unity had earlier 2 versions, one free with like 90 percent of the functions, and one pro version that you had to pay something like $1500 to get. But yesterday they released the pro version for free (But you have to pay Unity if you make money).
The first thing you notice in Unity 5 is that everything from the beginning looks better. The "hello world" of all game engines that also can handle physics is to build yourself a tower of cubes and then destroy the tower with balls. This is how it looks like in Unity 5:
Even though the images above look like they are still images, you can actually fly around. So I'm really excited what I now can do to improve my Tesla Simulator (which by they way is completely broken after the update because Unity changed a few of the physics calculations). And if you want to try out Unity yourself, there's a lot of tutorials on YouTube and on Unity's own site.