Android Question Send and receive a ping?

[Andromeda]

Some apps have a function that sends something like a ping. Phones with the same App can sense it and shows the possible apps around like a GPS-Signal. (Maybe its just possible through the sending of a GPS-Signal to the server) But can it be possible to do a Ping around?

How do they do it?
I want to sense this app..maybe in a distance of 2 or 3 meters and store that information. Is it something like an App-Ping?

 

[Erel]

It has nothing to do with GPS.

You can search for nearby devices based on Bluetooth if they are set to be in discoverable mode.

With some work you can find devices in the same local network using UDP broadcasting.
MQTT Chat with Auto Discovery

 

[Andromeda]

No. Not in the same network. Just having one app in one device. Second app in the other. And sensing each other or ping each other somehow. No lan connection. As far as i thought. You have to have a server that gets gps and compare the distance...but can it be done without it? Bluetooth would be too energyconsuming

 

[Erel]

Not trivial but possible with WifiDirect: https://www.b4x.com/android/forum/threads/android-wifi-direct-tutorial.30409/#post176526

 

[Andromeda]

I just want to transmit the ip-adress of each others...