What if the user supplied a token to a device at the location rather than the user collecting a token from the device? Depending upon how often you needed to co

What if the user supplied a token to a device at the location rather than the user collecting a token from the device? Depending upon how often you needed to confirm attendance, you could greatly reduce communications. You could also use the users device to power the locations device. Without more details from you it might be hard to come up with lots of ideas