Which Database and Language I should use?

I'm developing a software with database in C#.Net with SQL Server Database. Now i want my to access my data from online website, and android app. Before it, i'm going to try three different databases, then i didn't understand how i'll manage it. I know C#.Net, Java for android, and some of php too.

Have you any idea, which database and language i should use to access from 3 different platforms at a time.

For example: I put record in my database from desktop PC, then i want that record from my android app, and from my website at the same time.

Advance sorry for bad english..