The idea for this app grew out of a previous product that Square developed in 2009, which allows cell phone users to connect a credit card scanner to their headphone jacks.

2009年推出的一项产品。 通过这个产品，手机用户可以将信用卡扫描器与手机耳机接口直接相连。

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The iPhone features an integrated Web browser, tiltable 7.4-inch gray scale touchscreen, an e-mail client, a 56-kilobits-per-second modem, two phone jacks, a full duplex speaker phone, and a keyboard that slides under the phone to save space.

CNN: InfoGear upgrades phone of the future