for iPhone, Android, Windows 8 and maybe Blackberry.
Kees
I have developed an excel spreadsheet that provides analysis (including in charts and tables) across a number of sheets based upon a small amount of data the user enters in the first sheet. I want to run the spreadsheat enabling the user to enter the data and providing all the analysis but through the internet. I want to create a platform that is secure and can't be downloaded into an excel format, protecting all the formulas etc. I would like to include a forum and online payment.
I really want to develop this myself if possible but am not sure where to start. I have been looking at various options but am not sure if I should be using a database to set this up or if there is software that would make it easier. I'm prepared to put in a lot of time learning the likes of PHP and MySQL but don't want to spend a lot of hours on this if its not what I need to do this...
Any help gratefully appreciated.

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