Windows 8 supports sharing the data from one application to another with in built support through contracts.
Follow Data type packages can be passed from one application to another :
2. Plain Text
3. Formatted Text
7. Custom Data Formats
This blog has a getting started sample of contracts in action.
- Virtual Windows 8 Hands-on-Labs (blogs.msdn.com)
- 8 quirks Windows 8 XAML developers should understand before starting their Metro app (pluralsight.com)