If you are interested in developing Windows Phone 8 apps that would connect to SharePoint 2013.
The great news is Microsoft released SharePoint 2013 SDK for Windows Phone 8.
Install the tools:
1. Prerequisite: Make sure you have the Windows Phone 8 Developer tools installed on your PC.
2. Download and install Microsoft SharePoint SDK for Windows Phone 8 MSI.
Develop Windows Phone 8 apps for SharePoint 2013:
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