Why does OpenVPN on the iOS app drain my battery so fast?

The Proton VPN iOS app offers its users the choice of the OpenVPN, IKEv2, and Wireguard VPN protocols.

Learn more about the advantages and disadvantages of different VPN protocols(new window).

Some users have noticed when they select OpenVPN in our iOS app, the amount of battery power our app uses dramatically increases.

The issue lies in how the operating system reports battery usage. When you connect to our VPN using OpenVPN, the iOS operating system registers the network requests and responses of the other apps that use the VPN connection as belonging to the Proton VPN app.

Example:

If you watch Netflix on your iPhone without a VPN, the requests the Netflix app sends out to the Netflix server to load the next show are registered as battery usage for the Netflix app.

However, if you are watching the same show on the Netflix app while connected to a Proton VPN server via OpenVPN, those same requests from the Netflix app will count towards the battery usage of the Proton VPN app.

This happens with all VPN apps that offer OpenVPN on iOS devices.

Apple iOS devices have native support for the IKEv2 VPN protocol, which is why they more accurately track the battery usage of the VPN connections using IKEv2. That is why this bug only appears when you use the OpenVPN protocol.