Apple is sending out refund notices to iPhone users who purchased GameStore, the bizarre Apple app that briefly appeared in the App Store over the weekend.

You recently purchase the GameStore app. The app was made available for sale prematurely. We apologize for the problem and have refunded the purchase amount back to your account. These funds will be applied to your original payment method within 5 business days.

While GameStore showed a release date of Dec. 31, 2011 in iTunes deskstop, the on-device App Store showed a date of June 9, 2009, which suggested it might have been a beta app used to test the iOS 3 in-app purchases feature.

The refund language, however, clearly says “premature”, which would suggest it will be properly released at a later date.

Whether or not that’s accurate, whether or not a new app with the same name but more current functionality, or whether there’s a different explanation remains unknown.

Looks like Apple has begun the process of refunding Apple Online Store bumper case orders. *MacRumors says:

Existing back-ordered bumper cases have also been processed for refund. We expect the process will continue over the next few days. Apple is also expected to provide a method for in-store purchasers to also receive a refund but has provided no details yet.

As part of their iPhone 4 “antennagate” press conference, Steve Jobs announced Apple would be giving away free cases, including Apple Bumpers, to every iPhone 4 customer as a way to make them happy and alleviate any concerns about reception issues.

Anyone else get their refund notice yet?

[MacRumors]

TiPb contacted several developers to find out what was going on. While some were aware of the potential for a 100% refund charge back, none had experienced it. Uniformly, they reported very few refunds, and when they did occur, charge backs only for the same 70% cut Apple had originally passed along to them.

For now, at least, Apple is eating whatever processing, administration, and other charges that occur out of their own, 30% cut.

In general, all the developers we spoke with hadn’t seen many returns and didn’t seem to consider this a huge problem right now. This might be because the process of getting a refund is not easy to begin with. If that changes, as recently discussed on Twitter, it could become a greater concern.

As to Techcrunch’s other charge, that a refunded app becomes unusable, we’ve been unable to find an occurrence of that in the real world. If you’ve had a refund on any apps, let us know if it goes dead, keeps working but won’t upgrade, or stays the same.