Advice for Creating a Spreadsheet for Tablet & Other Spreadsheet Platforms

Hi all,

I am working on a project for some clients where I need to build a spreadsheet that can be used on a Tablet. My issue that I am having, is that most tablets do not have a MS Excel hardware option, besides the Microsoft Surface (maybe a few others). A majority of my clients will be operating the Ipad/Ipad mini or Android tablet which do not have a MS Excel software program. Many of my clients are using 3rd party spreadsheet apps such as Google Docs, Skydrive, Documents to Go, etc...

What is the best way to create a spreadsheet that is compatible with all of these different types of tablets that are on the market, as well as different 3rd party apps?

Also, any advice on overall design procedures or tips would be helpful.

Thanks in advance for your time!

Dave