The promotion includes the iPhone 4S when you checkout, although it is not labeled as participating in the promotion as the other smartphones are, so you can essentially get it for $50 from Sprint now. This is for new lines and your account has to be active for at least 30 days before the Amex $100 card gets mailed to you.
A few days ago, we passed along the speculation that Sprint was about to offer a free ZTE Optik tablet with the purchase of every smartphone
. Well, as it turns out, Sprint is giving something away, but it is not a tablet-at least not yet. From now through August 26th, purchase a new smartphone from Sprint and you will receive a $100 American Express Reward Card
There are some caveats as usual - you must make the purchase of the smartphone online, and your account has to be active for at least 30 days before the card gets mailed to you. You can otherwise select any model, though, including those that are free with a two-year contract. Models that will be launched before the 26th of the month are also part of the promotion, such as the Motorola PHOTON Q 4G LTE
which is set to be released on August 19th
source: Sprint via UnwiredView