Hi all, 

first post here, but I've read loads in the past.... and figured you clever cookies would be able to solve this problem for me :) 

Im wanting to make a bluetooth switch...

these are the parameters of it. its pretty basic in operation.

it needs to operate a 15 to 16 amp contact 230v relay.

it needs to turn the relay on when you are in range (30 meters or so).

use of a smart phone is the source of the connection to turn the relay on. 

has to cost under 20 to 30 dollars NZ to build.

and maybe 4 or 5 smart phones can connect to it when in proximity to active the relay.

it also should not require an active part on the smartphone to activate the relay As in the user doesn't have to open an app to make it work). 

the nuts and bolts of it is.... when you come in close the relay is on, when you walk away it is off. ..

I have a few ideas but know they have a few problems.

can anyone offer some advice, or even a product that does this already?

Cheers Paul :)