the nsec remote signer doesn't need to stay online 24/7—it's a hardware device you connect via wifi or usb only when signing events, keeping it mostly air-gapped and powered off otherwise, unlike always-connected phones.
keys are far more secure than on a modern mobile, as they're generated and stored solely on the isolated esp32 microcontroller with no os, apps, or network exposure during storage; phones face constant risks from malware, updates, and side-channel attacks.
