SMS message or BMS to everyone who passes your booth?

I have a client in USA who wants to have a message sent to everyone's phone who passes his booth. From what I understand SMS spam is illegal and serious business if you get caught. I heard about proximity marketing by using a Blue Tooth device that will ask the person if they want to connect then you can send them a file. Obviously they need Bluetooth turned on so we can have a sign asking for that, but I haven't gotten a conclusive answer if this will work in the US. I saw a couple posts saying this wouldn't work on iPhones or Blackberries. Can anyone give me a concrete answer if this will work?

Yes it would be illegal if a message is sent to everyone who passes his booth. However, he could put some type of promos, coupon, free estimate of services info at the booth with a short/long code number to get prospects. Check out the short code association website to find out all the legalities related to text message marketing. Good luck with everything.

Zero Proximity Marketing out of Australia has a device for a trade show booth.
I don't think the message is illegal. They would get a 300 character message
asking permission to read the full message.

Check out their other products. Some are waterproof for outside a building. The range
is 300 feet. You can drive around with one and broadcast to 14 or 28 Bluetooth enabled phones. Another version with an array can cover a sports stadium.

They also have a network of advertisers in the US for these devices.

Another company with proximity devices is BlueMagnet. A little less expensive, but
not waterproof.

Hey I did not even know about BlueMagnet! That is amazing, I just checked out their website.