The practical application of knowledge, especially in a particular area, is called technology. Advances in technology affect every area of our lives. This category is for questions about technology and includes everything from how to remove a scratch from a CD to applications of electronics to what polyester is made from and more.
Well, if I'm getting what you're saying, if it's an app that's like a safe, then typically speaking you would probably make your own combination. I'm not sure if that's what you were talking about but hope this helped :)