NTT DoCoMo has this solution for couples who spend a lot of time talking on the phone. It's called the Taion Heart, a mobile accessory for phones.
Each person gets a heart that they grip in their hand. The device measures your pulse in order to represent how fast your real heart is beating while talking on the phone to your sweetheart. The info from the heart is then sent via Bluetooth to the other person's phone and then to his or her own heart. When the heart heats up, vibrates, or its lights change colour, it's meant to communicate how a person's partner is feeling about them at that moment.
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