Use APKPure App
Get Network discovery old version APK for Android
Pings all devices in a specified network and grabs their hostnames
This app can be used to find all online devices in your, or any other ,network, specified by IP and subnetmask. The devices responsetime and their hostnames are saved and stored for later use. You can customize the number of threads used (may slow your device when using to many threads, be careful) and the timeout (The time a host has to answer before being marked as offline).