Tempo windows
Tempo is measured over 1, 4, 8, 16, 32, 64, and 128 beats. Short windows react straight away; long windows show the overall trend. The 16-beat trace is highlighted as the main trend line.
Tempo tracking for iPhone
Ian's BPM
See how the tempo of a live performance changes as it happens. Tap along with the beat, or let the microphone find it, and watch scrolling traces show both beat-to-beat variation and the longer-term drift across a whole medley.
Manual mode
Tap along with the beat
Choose Manual at the top of the screen and tap anywhere on the graph once per beat. The session clock starts with your first tap. You don't need to look at the screen to tap; the whole graph area is the tap target.
Markers and tune changes
Tap the pin to drop a marker, or the music note to mark a tune change, without stopping. You can name them afterwards, for example March, Strathspey, or Reel.
Stop and save
Tap the stop button, then choose Save Session to review and save it, or Reset Without Saving to discard it.
There is deliberately no Undo button during a session: by the time you reach for it, the music has moved on. A stray tap shows up briefly in the short windows and has little effect on the 16-beat and longer trends.
Auto mode (experimental)
Let the microphone find the beat
Choose Auto and allow microphone access. The app waits for the music to start, settles on a steady pulse, and then records beats automatically, driving the same graph and statistics as Manual mode. Audio is analysed on your iPhone in real time and is never recorded.
Tempo multiplier
If the detected tempo is a related multiple of the beat you want (for example half or double), move the multiplier slider. The whole session is recalculated at the new tempo and keeps its ups and downs.
Detection sensitivity
In Settings, raise the sensitivity to pick up quieter beats, or lower it if the app is reacting to notes between the beats.
Markers and saving
Once the session clock is running, the marker and tune-change buttons work just as in Manual mode. Stop to save or discard the session.
Auto mode is still being tuned. For important measurements, Manual mode remains the most reliable reference.
After the performance
Review, rename, and export
Saved sessions appear in Previous Sessions (the clock button), where you can search, reopen, or swipe to delete them.
Full-session graph
See the complete performance with your markers, rather than just the last minute or two.
Statistics
Duration, average tempo, starting and ending tempo, minimum and maximum, and the total change from start to finish. Add a target BPM to see how far the ending tempo was from it.
CSV export
Share a session as a CSV file containing every beat timestamp, the tempo for each window, and your markers, ready for a spreadsheet.
Preferences
Settings
Tap the gear button at the top of the screen.
General
Choose whether the app opens in Manual or Auto mode, and turn on a light haptic tap (off by default, as it can influence your timing).
Graph and traces
Set the live graph to show 60, 90, or 120 seconds, choose 8 or 16 beats for the minimum and maximum statistics, and hide traces you don't need. Hidden traces are still saved and exported.
Auto mode
Set the starting tempo multiplier and the detection sensitivity from 0 to 1.
Help
Support
Questions, problems, or suggestions? Email ian.blackwell@gmail.com. It helps to include your iPhone model, iOS version, and the app version shown in Settings.
Why is there no tempo until I've tapped a few times?
Each window needs enough beats to measure across. The 4-beat tempo appears after five taps, the 16-beat after seventeen, and the 128-beat after 129.
Auto mode isn't starting.
It waits for a short burst of sustained music before the clock starts. Check that microphone access is allowed in the Settings app, and play closer to the iPhone.
Auto mode shows half or double the tempo.
The detector sometimes locks onto a related pulse. Use the tempo multiplier on the Auto screen or in Settings to correct it; the session is recalculated.
Does the screen stay on?
Yes. The display is kept awake during a session and returns to normal when you leave the live screen.
Where is my data stored?
On your iPhone. Nothing is sent to the developer; see the privacy policy for details.
Can I use it in landscape?
Yes. The live screen is designed for landscape, with a stats rail beside the graph, and also works in portrait.