This document summarizes several papers on crowd-sourced video sharing systems. It discusses issues with sharing redundant videos of the same event which uses significant bandwidth and battery. Approaches proposed include on-demand retrieval where metadata is uploaded and videos fetched only when a query matches. The Movisode system allows spatiotemporal queries and uploads metadata instead of full videos to the server. However, it has disadvantages as video retrieval depends on network strength and may be time consuming. Overall, the document reviews techniques for optimizing video storage, sharing and querying to minimize costs and resources.