Sprint doesn't offer "insurance" for devices but three types of equipment protection coverage options. Below is a description of the programs taken from internal Care documentation. You can also visit http://shop.sprint.com/en/services/service_repair/index.shtml for more information.
TEP = Total Equipment Protection
ERP = Equipment Replacement Program
ESRP = Equipment Service Repair Program
Check out a fun infographic that teaches you how to increase storage, enhance security, improve battery life and clean your device.