The hardware is cheap and small, so a radio can fit into a ring-size device.

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Researchers measured brain activity of 47 healthy adults -- a small but scientifically valid size group for this type of study -- while using a mobile device.

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Out-of-the-box, the LeafPresenter provides small and medium size businesses (SMBs) with a feature-rich mobile ordering and checkout device capable of accepting payments via their choice of processor or next-generation payment methods such as PayPal, LevelUp and other mobile wallets.

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As you can see above, the device is actually quite small, and most smartphones would have quite a bit of trouble fitting into a box that size.

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