What I like about the command line version of Fing is that it's fast, flexible, easy to integrate with other applications (it even outputs results in an XML format) and you can install it as a service under Windows.
The iOS version of Fing is slightly different: It has a GUI and a simpler goal -- to scan whatever Wi-Fi network your iDevice is connected to. When you launch Fing it lists the devices it finds, their type, IP address, vendor name and MAC address. The discovery list is saved under the access point's SSID and you can email the findings directly from the app.
For large networks there's a search feature so you can restrict the list to just the entries that match the search string. You can also view details of the access point (subnet, BSSID and SSID) and the ISP (ISP name, geolocation, external IP and external IP name).
Fing is simple, fast, very useful and all versions are free! And, wonder of wonders, they are all also free of ads! W00t! Overlook's Fing gets a rating of 5 out of 5!
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