91VPN is a free utility tool developed by GIGADGETS INC for iPhone users. It offers support for v2ray, trojan, vmess, and shadowsocks protocols, allowing users to access premium nodes in the United States, Germany, and Singapore.

With 91VPN, users can easily configure their shadowsocks, socks/socks5, and vmess/trojan server information. The app also has a feature that detects and inserts server nodes when users copy a valid JSON format of a v2ray client configuration. Additionally, users can conveniently add new nodes by scanning QR codes generated by ss or vmess protocols.

It is important to note that the v2ray server is installed or created by the user themselves. The app does not collect any user data, and all the data generated by the software remains on the user's device. Furthermore, users have the option to subscribe to the premium service, which removes ads and provides access to VIP nodes.

Please refer to the user terms provided by Apple and the privacy policy of 91VPN for more information.