Proton VPN has discontinued support for the OpenVPN protocol in its Android application as of February 17, aiming to enhance user experience by promoting faster protocols like WireGuard and its proprietary Stealth protocol. This change reduced the app's size by approximately 36% and was driven by the fact that OpenVPN was used by less than 1% of Android users. The transition to WireGuard and Stealth improves performance with near-instant connection times and reduced battery consumption. OpenVPN can still be accessed through third-party configurations on Proton's servers.