Developing An App

Greetings

I was wondering what free programs or websites are available for developing a fully interactive app or a simpler app where you can just click to switch pages.

I am admittedly not the most technical or been the best with computers but I believe I have come up with a strong app idea which I think could sell and which I would prefer to make myself which may be very unlikely but it would be a good hobby to take up in my spare time and I am well aware that it will not be an easy task but one of the main problems are that I am not willing to put any money into it at this point in time and would prefer not to put any money into the app during the whole process.

Please could anyone tell me a good free ipad/iphone app developing website plus the code which I must learn to make the app and a free site I could learn the code from. I would prefer it to be fully interactive but obviously I am a beginner and am quite aware that it is unlikely that I shall be able to make this however I fell its always good to set a high goal so even if I do make the app and everything, I can still always work on a second interactive more effective version.

Thanks a lot for anyone that can help