Apps similar to NetworkToolbox - Net security include Angry IP Scanner, which is free and open source. Other options are Fing, Advanced IP Scanner, NetPeek and Port Authority. You can choose from more than 10 IP Scanners like NetworkToolbox - Net security for Windows, Mac, Linux, Android and iPhone.
NetViews is a modern, macOS network scanning app inspired by the specialized needs of IT, Wi-Fi, and network professionals. It combines host discovery, Wi-Fi insights, real-time monitoring, and vendor/DNS insights with a clean, native interface - giving you the tools you need...
United States
iNet provides you with information about networks your iPhone or iPod touch is connected to. Its very easy and user friendly design even allows the unexperienced user to get a profound and understandable overview of a network and the running services.
Germany
EU
LanScan Pro is a simple and efficient IPv4 network scanner that discovers all active devices on any subnet: the local one, or any public subnet that you configure.
FranceEU
Netdiscover is an active/passive address reconnaissance tool, mainly developed for those wireless networks without dhcp server, when you are wardriving. It can be also used on hub/switched networks.
This specialized application allows you to perform periodical checks of multiple hosts, IPs, websites and, if required, even ports.
GermanyEU
grIP is a console-based, multiplatorm TCP port scanner with support for IPv4 ranges as well as individual IPv6 IPs. It will shuffle the scan range and utilize a configurable number of sockets to scan it in parallel.
DeviceShelf is a local-first alternative for people who want to see every device on their network without an account, telemetry, or a subscription.
Switzerland
