NordVPN is a virtual private network from Nord Security. Its own site describes Threat Protection, which blocks ads, trackers, and malicious sites, and Meshnet, which links a person’s own devices. It also lists specialty servers, including Double VPN and obfuscated servers, for traffic that needs an extra hop or a less obvious VPN connection.
Apps are offered for common phones, computers, and browsers. One subscription can cover several devices at the same time, within the plan limits NordVPN sets. NordVPN states a money-back guarantee on plans it sells itself. Which specialty server is available depends on the plan NordVPN is selling.
Where this page shows an Up to cashback rate, that rebate is from KPON, not from NordVPN, and it follows the terms above.