Short answer: tested a bunch of providers with WireGuard on mobile. Big shocker. Some barely sip battery, others devour it faster than my ad budget gets spent. Thought I'd share what I found, in case anyone else is fighting with the same PITA. ProtonVPN and Mullvad? Great on battery. NordVPN? Kinda meh. Surfshark? Blew through juice like it was free. Protocols are not all equal, even when using WireGuard. Seems like some apps are just better optimized. TL;DR: pick your provider wisely, test for your use case, don't assume all WireGuard configs are the same. Hope this saves someone from wasting hours. Still fighting with this for a campaign - I swear, VPNs are the gift that keeps on giving.