The Challenge with IoT and VPNs
Most smart home devices (smart speakers, cameras, thermostats, light bulbs) cannot run a VPN app directly -- they have no interface for software installation. To protect these devices with a VPN, you need to set the VPN up at the router level, so all traffic from every device on your network is routed through the VPN tunnel. This works, but it comes with tradeoffs.
Router-Level VPN Setup
If your router supports a VPN client (many Asus, Netgear, and DD-WRT routers do), you can configure your VPN provider credentials directly in the router settings. All devices connected to that router then use the VPN without any per-device setup. Limitation: the VPN encryption happens on the router CPU, which can slow down your internet connection significantly on budget routers. Routers with dedicated VPN hardware (like some Asus models with hardware-accelerated WireGuard) handle this much better. Alternative: buy a pre-configured VPN router from providers like Aircove (ExpressVPN) or Vilfo.
What a VPN Protects in a Smart Home
Traffic encryption between your devices and the internet: ISP cannot see what your smart devices are communicating. Hides which smart home platform you use from network-level observers. Protects devices from IP-based tracking when they call home to manufacturer servers.
What a VPN Cannot Protect Against
Security vulnerabilities in the device firmware: if your smart camera has an unpatched vulnerability, a VPN does not prevent exploitation. Local network attacks: a device on the same WiFi network can still communicate with and potentially exploit your IoT devices -- VPN does not affect local traffic. Data collection by the manufacturer: the data that smart home companies collect (your voice commands, usage patterns, etc.) goes through the VPN tunnel encrypted, but the manufacturer still receives this data once decrypted on their end. A VPN protects the transport, not what the manufacturer does with your data.
Practical Recommendation
For most home users: a router-level VPN is more effort than it is worth for smart home privacy specifically. The bigger smart home privacy levers are: buying from manufacturers with strong privacy policies, disabling features you do not use (microphones on devices that do not need them), and keeping firmware updated. If you already use a VPN for other reasons and have a compatible router, enabling the router VPN is a reasonable addition -- but do not set it up primarily for smart home protection.