After checking (and buying)  many apps two of them are really good (personal opinion of course)

IP Network Scanner

There is the “Lite” free. It is limited no of devices displayed on network. It is full functional.

IP Scanner scans the local area network and determines the identity of all internet devices on the on the network.

• It allows you to chose name and image (from its library) for any of them.
• Display basic details (IP, MAC address and manufacturer of it is available)
• Get open ports (standard) and allow you to connect to the device using a “tap”.
• Allow to  setup way of scanning (aggressive or not)
• Allow to export /save / mail the list of device s and details

.. and much more

Fantastic toll and heavy used by be to get fats the network topology of my clients and

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