"I have no idea what Apple or Google are doing software wise, if they have the equivalent of C# and .NET."
Apple has objective C which you use with XCode, and Google uses the original .NET. It's called Java. It was created far before Anders Hejlsberg, the MSJVM WFC lead(remember J++), decided to "borrow" it when Sun told him he couldn't create non JNI Win32 extensions.
that I know. It is news from many years ago. I have no idea if Apple is using its abundant smarts to improve or replace objective C. Maybe a runtime framework that enables secure code to be written, yet provides all the great programmer productive features of .NET and C#.