Bluetooth LE (SMART) with nRF51822 onboard
If you are looking for a powerful BLE module capable of a standalone operation, probably the MBH7BLZ0X module is the right choice for you.
Does a universal signal relay exist?
To tell the truth, probably no, but we have for you a few hints for relays which are very close to an ideal.
Slim, humble and long-age - this is the Fujitsu FTR-MY relay
Despite a low power consumption this relay handles 5A/250VAC while maintaining a considerably long lifetime.
Narrow but strong - relay Fujitsu FTR-LY
With its width of only 5mm is this relay able to switch 6A/250VAC, moreover at a minimum coil power consumption.