But the gift contract is a unilateral and gratuitous contract. So to protect the donator's benefit the Law should allow the donator to have the right of revocation in some special situation.

但因赠与合同系单务、无偿合同，所以为维护赠与人的利益，法律应于特殊情形下，允许赠与人撤销赠与。

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One team offered him a thirty thousand dollar gift just to sign a contract agreement.

VOA: special.2010.04.11

Smartphones require more thought given that it has to be tied to a carrier and the gift receivers phone may not have fulfilled the contract term.

FORBES: Huge iOS and Android Activity on Christmas Day

Some of the contests will feature the actual phone (carrier branding may vary), while others will offer an Apple Store gift card to cover the cost of buying one without a contract.

ENGADGET: Introducing Engadget's next giveaway: Five iPhone 5s in five days!

That small amount of profit would come after you received your Buy-Back credit in the form of a Best Buy gift card and absorbed the penalty of breaking your two-year phone contract, commonly known as an early termination fee (ETF).

FORBES: Best Buy: Yes, You Can Make A Profit From Our New Buy Back Program