Barometric elevation logger for iPhone. Reads your pressure sensor, not GPS. Counts metres climbed, descended, and stair-equivalents.
Tap Start before a walk, hike, or trip up the stairs. AltLog reads the iPhone's built-in barometric pressure sensor (the chip behind Apple's Floors Climbed metric) and tallies cumulative ascent, descent, and stair-equivalents in real time. Tap Stop when you're done — the session lands in History as a scrubbable altitude profile.
Pressure is plentiful and free. It works in parking garages, multi-story buildings, stairwells, elevators, and dense forest where GPS struggles. Battery cost is negligible: a long city walk costs you a single-digit percentage of battery.
No account. No cloud. No analytics. No third-party SDKs. All pressure samples are processed on-device and only a downsampled summary is stored in SwiftData. Deleting the app removes everything.