HomeAppsToolsKnock on PortsApps like Knock on Ports Here are some great alternatives to Knock on Ports by Alexander Yaburov : UDP Guard ★4.4 Ping: test high latency, delay ★4.1 TCP Ports list ★4.6 UDP TCP Server ★3.9 UDP Sender / Receiver ★3.2 NoobzVpn ★4.7 Port Authority - Port Scanner ★4.1 UDP Terminal ★3.9 ALFAISAL Inject ★3.9 TCP UDP Server & Client ★4.5 Packet Injection ★3.8 Knock In VIP Messenger ★3.4 Fast Port Scanner ★3.5 UDP/TCP Widget ★4.9 STU for NAT ★3.5 Advanced PortChecker ★4.3