Websites and apps

I have recently started looking at getting an app made for my game Fortune and Venture and there is a minefield of information from flash, html5, android etc. I also have to make a decision on whether I should get the app made solely for the I phone which has its own platform or for the rest of the app users who don't use Apple products. When I do talk to the app makers I have also got to think how it will transfer across in terms of functionality etc. I cam across a great article for those of you at school / college who make websites and are thinking of making app  - the dos and donts of web and app design. Let me know what platform you would choose if you were me.