connect to non-discoverable bluetooth device

Question

I am developing an app for android. Just a general questions as to , if is it possible to connect to a device which is non discoverable publicly?

Thanks in advance.

Answer 1

According to documents NO, but maybe there's a backdoor as always we see hackers find them while the manufacturers have leaved it for their private use or helping governments finding crimes (like mobile technology).

Answer 2

The point of the device bieng in non-discoverable mode is that it won't accept connections. So, unless the device has been connected while the bluetooth device was in discoverable mode, then I don't think there is a way to accomplish what you are trying to do.

And I'm sure a hacker has found a way to do it already, but only by hacking the bluetooth device itself, so that it accepts connections while indiscoverable -- but why would you want to do that in an app?

I've also looked around on a few other forums and the common answer is no.

Answer 3

By discoverable I assume you meant responding to device searchs from another device. Some manufacturers also refer to it as visible. Depending on the manufacturer of the device , some devices allow Bluetooth to be on and visibility/discover-ability to be set to off. So if you already know the Bluetooth Address (MAC Address) of the device you can directly connect to it even when the device is not discoverable/visible. In practice it is a good thing to do, many manufacturers allow for this by having the device visible only during specific periods like during the paring process or have explicit menu option to turn on discover-ability for a specific period. This is a good practice from a security stand-point as it prevents device tracking / hacking.

iPhone for example is by default non-discoverable when Bluetooth is on, (but you can still connect to it) it is only discoverable when you enter the Bluetooth menu from the settings menu.