An app to provide real-time audio feedback on endurance exercise cadence, heart rate, and speed. Can also log the signals onto the smartphone memory.

Of note, has high power consumption. Android will turn the app off automatically unless you whitelist the app manually for ignoring power optimisations (something akin to Settings -> Battery -> Energy Saver -> Exercise Pacer and turn the selections for power consumption optimisations off).

FEATURES
-Audio feedback on Heart rate (from an external bluetooth heart rate monitor), speed (based on the smartphone GPS data, if available, and step rate (based on the smartphone accelerometer signal)
-Select feedback language and voice (uses Google Text to Speech, which has many languages on offer)
-Adjustable feedback interval (10 s to 600 s)
-Toggle audio feedback on/off
-Toggle heart rate, speed or cadence feedback on/off
-Log raw data (can toggle on/off)
-Toggle units for speed between m/s or km/h and cadence Hz or cycles/min

OF NOTE:
-Depends on an external Bluetooth heart rate monitor for heart rate
-GPS cannot be activated programmatically so you will have to enable GPS manually, otherwise it cannot be logged. You will first need to enable location, and then go into Mode and select 'Device only' or 'High accuracy' to enable the GPS.
-Cadence estimation is challenging, and will fail occasionally, and will work better for running compared to other activities. Wear location (pocket, phone holder on the arm, hip etc. will also affect the cadence estimate. For most useful information wear your smartphone on the same location on each use.
-Cadence (steps per second) based on least-squares-spectrum analysis (essentially by implementating the method I reported in Rantalainen et al J Appl Biomech. 2016 Aug;32(4):401-6. doi: 10.1123/jab.2015-0266.).
-Data logged similarly to my GPS Logger, Accelerometer Logger, and Bluetooth LE Heart Rate Logger apps. The logs can be inspected with my

HR Log Review,
Cadence & Distance from Accelerometer &
GPS Log, and GPS Log Elevation Fetch
apps.