NFC in the smartwatch what is the use?

[Smith 001]

Recently I saw some NFC smartwatches, I'm curious about what the NFC is used for.
I know NFC is used for Samsung Pay in Gear S series, but how about others, other watches use this NFC for what.

 

[jasonandrews25788]

Google readying tap-to-pay for Android Wear smartwatches
If you have a compatible Android Wear watch (one with an NFC chip), it will let you touch your watch to an NFC-equipped retail terminal to pay for goods.

 

[Smith 001]

Google readying tap-to-pay for Android Wear smartwatches
If you have a compatible Android Wear watch (one with an NFC chip), it will let you touch your watch to an NFC-equipped retail terminal to pay for goods.

So NFC can only use for payment? Thanks for your reply.