You sure can, But they may charge you a $35 restocking fee.
We are committed to making sure you are satisfied with your purchase. If you’re not, simply return your undamaged device and deactivate services within 30 days. We’ll refund your activation fee and waive your early termination fee as long as you return your device. For all purchases made on or after 4/19/09, a $35 restocking fee will be charged (at time of exchange, not billed to account) to exchange a device that has been activated for a different model or color or if you swap back to customer owned equipment and return the new phone. Read the details. Please note that this policy may not reflect the policies of Sprint partners.
Check out a fun infographic that teaches you how to increase storage, enhance security, improve battery life and clean your device.