Yes, when the application initially loads you can "Not Allow" access to your contacts. However, you if have already allowed access follow the below steps:
- 1. logout of the application via settings
- 2. completely kill the application through application management
- 3. go to settings -> privacy -> contacts
- 4. find StarPhone which currently should be on and slide the indicator to off.
(Note) On IOS5 or before users will need to uninstall the application and when the application asks for access to the contacts you must select "don't allow".