writting apps that run on phones and dial phone numbers

[Kirsten Greed]

Hi All

 

Can anyone give me an idea how to write an app that runs on Android and/or
iphone and/or windows 7 phone 

The user would search for a contact and then press a DIAL button

The contacts database would sync with the corporate one  ( via Microsoft
Sync Framework I expect )

 

Where do I start?

 

Thanks

Kirsten