Apple has published the details of how iPhone 4 owners can refund an existing bumper and order a new case or bumper for free.
If you purchase an iPhone 4 before September 30, 2010, you are eligible to receive an iPhone 4 Bumper or a select third-party case from Apple at no charge.
Apple has made the process simple for iPhone 4 owners, just download a specially built iPhone app from the App Store [iTunes link] and pick what case you want and it's as simple as that. Apple is offering 7 third-party cases alongside its own black iPhone bumper.
Apple has also offered instructions to those who already purchased an iPhone bumper. Those who purchased online or through a retail store using a credit card will see automatic refunds. Those who bought a bumper using cash or gift card will need to return the receipt to an Apple store before September 30 for a refund. Apple's refund will include any taxes and shipping charges.
