Smart phone apps

If you have an idea for an app, How do you go about making one? Can you download software to DIY or do you give the concept to someone and they develop it for you?
The Idea I have is actually very simple and in the right hands wouldn't be very hard to create.
I don't even have a smart phone myself so I'm possibly not the best person to go forward with the concept.
How do you go about this?
Jeroen
The Idea I have is actually very simple and in the right hands wouldn't be very hard to create.
I don't even have a smart phone myself so I'm possibly not the best person to go forward with the concept.
How do you go about this?
Jeroen