Best Buy is offering free invisibleShield film to iPhone 4 owners, according to a leaked internal flyer. Engadget reports that the retailer is offering free invisibleShield side film to iPhone 4 users in order to offset potential antenna problems, and possibly to up-sell customers on a full film set or case. In addition, the offer reportedly extends to all iPhone 4 users, not just those who purchased their handset at Best Buy. Calling your local store…
