ben-z/findphone

findphone is a command line tool for macOS that helps someone locate a nearby Bluetooth device by tracking its signal strength. It was built for situations where Apple's Find My feature is not available, for example when a device is enrolled in mobile device management software that disables it, but the device is still close enough to be within Bluetooth range. The tool can be installed by downloading a prebuilt universal binary from the project's releases page and clearing the quarantine flag macOS adds to unsigned downloads, or built from source using the Swift toolchain, which requires no external dependencies. It needs macOS 13 or later. There are three main ways to use it. Running it with no arguments surveys every nearby Apple handheld device by signal strength. Running it with a device name switches to hunt mode, tracking one specific device. A list option shows paired devices and their addresses. In hunt mode, adding a sound option produces clicking sounds that speed up as the signal gets stronger, similar to a parking sensor, so someone can search a room by ear instead of watching the screen. This is not like a Geiger counter: the click rate comes from a smoothed reading on a fixed timer, not from counting individual detected signals. A redact option is available for anyone recording their screen while using the tool. It hides Bluetooth addresses and, in survey mode, replaces device names with just the device type, since a stable hardware address could reveal information about someone else's device. Names typed in hunt mode and names shown by the list option stay visible on purpose, since picking a target requires reading them, so the list option is not considered safe to record even with redaction turned on. Signal readings are shown in decibels relative to a milliwatt, a unit where numbers closer to zero mean a device is nearer, and the README gives rough distance ranges from arm's reach up to far away or behind an obstruction. The tool pulls readings from three different Bluetooth data sources of varying quality and only counts a new measurement when the value actually changes, since one source on macOS refreshes only every few seconds even when polled faster. It cannot make a device ring and cannot indicate a direction, only a rough distance, and it requires Bluetooth permission granted to whichever terminal app runs it.