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Because of the new Google policy, the app is not updated anymore on the Google Store

Now, the more recent versions may be downloaded there. Warning: only phones with Android 4.4 to 13 are supported and more recent Android version will not be.

Description:
Bike computer to ride faster by improving your aerodynamic position and testing gear/equipment. Among other data, it monitors CdA (drag*area) and Crr (rolling resistance) coefficients, during races or dedicated testing sessions. It requires BLE or ANT+ power and speed sensors, and an anemometer (option, see below) for improved precision.
Powermeters successfully tested are:
-Power2Max
-Assioma pedals

-PowerTap hub (records speed so additional sensor is not needed)
Speed sensors currently supported are:
-CycleOps
-Garmin (Warning: old Ant+ Garmin model is not working with the app)
-Wahoo
-CooSpo

Avoid any magnet less speed sensor, their accuracy is not as good.

Read the help to quickly see how to use the app: http://cdacrr.blogspot.fr/p/help.html

If you need help, you may post on Slowtwitch forum, on this thread .

Current features:
-Compare Crr between different tires on ridden laps at slow speed (<15km/h)
-Compare your CdA between different positions on ridden laps at high speed (>25km/h)
-Configurable field to switch between different fields (altitude, cadence, bike direction,...)
-Model uses air density accuratly computed with weather station data and detected sensors
-One FIT file and several CSV files are stored and can be sent by mail for post analysis
-Hear/record voice message each lap
-Activate cloud storage to list/edit previous runs later
-Plot virtual vs real elevation (barometer needed)
-Measure road vibration with phone accelerometer if available
-Wind forecast on location where you plan to field test
-Enable/disable auto-zero feature of ANT+ powermeter

The app is free, but more features are available with the premium version:
Premium features:
It includes other modes (described here):
-Defined lap length mode (for velodrome, click once to start the run)
-Time trial mode (needs barometer) to get CdA at the end of the race
-Criterium mode to get apparent CdA lap per lap during a race
-Training mode
And some optional devices:
-Support Weather Meter anemometer to record air speed (to get higher precision for CdA numbers during windy days)
-Possible to use Bluetooth headset to hear/record voice messages (useful during velodrome testing)

Download the key for the premium version here

Known bugs/possible issues:
-Recent Weathermeter are not supported
-BLE connection with older phones is sometimes tricky
-Random ANT+ dropouts
...

Release Notes:
4.1.0
-(UI) Enable user to delete all their recorded data to conform Google privacy policy
-(Model) List of sprockets may be defined into the settings for better estimation of the current gearing
-(Model) Virtual mass metric added for climb (increase in VM means either: higher CdA, higher Crr, elevation upward drift, less chain loss)
-(Mode) Some small changes for criterium mode: autostart added and NP instead of AP when printing each lap
-(File) Try to fix possible duplicated lines in Raw.csv file
-(Device) WeatherFlow SDK updated to support recent models
-(Data) Add headwind ride %
-(Data) Add weekly TSS, CTL, TSB metrics for training. Average efficiency (P/Hr) is computed 3 minutes after lap began
-(Fix) Fix GPS calibration process of BFV if last one drifts during first seconds
-(Fix) Extrapolation of pressure data during (rare) BFV disconnections
-(Fix) Gear estimation
-(Phones) Android 13 supported
-(Fix) Incorrect correction for barometer elevation during Crr test
-(Info) Print all battery levels when leaving app

4.0.1
-(Fit) Add developer fields with bike speed and headwind for Golden Cheetah import
-(Fit) SDK update from 21.47 to 21.67
-(Phones) Android 12 supported
-(Fix) Bluetooth autorizations added for API 31 (Android 12) and above
-(UI) Add screen auto lock option + disable some alerts + BFV/WM devices may be launched while riding
-(Field) Add inner chain-ring into settings for climb metrics and improved chain loss metric

4.0.0
-(Hardware) Automatic reconnection for WM and BFV devices (random link loss is possible on some phones)
-(Hardware) Support the BLE Windmeter (WFANO-01) from WeatherFlow. Cheaper, it records airspeed but has no temperature, humidity and pressure sensors
-(Field) Add ride energy, training load and intensity on lap/run/ride
-(Mode) Better detection if a ride is indoor/outdoor
-(Field) Add headwind lap percentage time
-(Field) Add left/right power balance data from Power2max power-meters
-(Phones) Android 12 supported
-(Output) Fix crank torque calculated values
-(Sensor) Calibrate the second aero sensor if any by the first aero sensor
-(Output) Add VE plot with estimated yaw correction (Run.csv file)
-(Output) New file Climb.csv created after each climb
-(UI) Show estimated Crr rolling average during climbs if BFV altimeter and aero sensor are used
-(Training) Differentiate FTP for indoor/outdoor and TT/road bikes
-(UI) Possible to switch between indoor/outdoor training session and between road/TT bike
-(UI) New climbing metrics: 5s slope (%) and VAM (m/h). High accuracy thanks to BlueFly vario barometer.
-(Hardware) BlueFly vario with airspeed shield is supported as an aero sensor
-(Mode) Time average should not contain any coasting (possible braking) for CdA real-time
-(UI) Can use only either BLE sensors (default) or ANT+ sensors. Switch it quickly by clicking on the BLE/ANT+ icon
-(Training) With training mode, detect sprints above 200% FTP and give some metrics
-(Hardware) Support BlueFly variometers v11 and v12 (added also as temperature sensor + set best hardware settings for CdaCrr)
-(UI) Try to automatically connect to previous searched sensors
-(UI) PowerTap hub automatically set as second power/speed device
-(Mode) Real-time CdA precision (default is +/-0.005, 45s@40kmh with BFV): more precision will need longer time to average

3.1.0
-(Mode) Add a new out and back mode with GPS detection
-(Mode) Automatic segment mode removed

3.0.3
-(UI) Support Bluetooth remote shutter. Click with it instead of using volume buttons when screen is locked
-(Mode) Error and possible crash with real-time CdA feature. This feature is disabled if anemometer is not used
-(Model) Braking model removed
-(Fix) Measured elevation was not normalized on plots + add some error metrics max|VE-H|, mean|VE-H|, ||VE-H||

3.0.2
-(UI) Anemometer is added to the list of searched devices. Bluetooth is not switched off after anemometer disconnection.
-(UI) Battery level (%) for BLE powermeter printed on the screen
-(Fix) Few bugs

3.0.1
-(Fix) Real-time CdA issue with virtual elevation, add option to enable/disable it
-(ANT+) ANT+ devices are not searched by default (should be enabled into the settings)
-(Mode) Add again the option to manually change the defined lap length

3.0.0
-(BLE) Power/Speed/HeartRate BLE sensors are supported. Click on "Power(W)^" and "Speed(km/h)^" to switch between sensors if any
-(ANT+) Dongles are not supported anymore
-(ANT+) Smooth 4hz speed sensor data with 1 second average (app bug which may explain the results with higher variance on velodrome)
-(Mode) Lap length for the "Defined lap length" mode should now be specified by clicking twice: at the start/end of the first lap of your first run
-(Model) Fix a bug in the real-time CdA feature + show time average which depends of the barometer precision (the better the latter, the lower the former)
-(Model) Smooth air density variation and disable pressure/temperature updates from weather station
-(Model) Two estimated CdA values into the settings: one for Crr test and one for mass estimation during climbs
-(Model) Add a new field Power@Sea level for training (use Peronnet formulae for power loss with altitude)
-(UI) Add real-time CdA for the modes not using altitude: the CdA moving average is computed on the lap length
-(UI) Click on "Temp [°C]^" to switch between temperature sensors
-(Fix) No CSV files created if logging disabled

2.5.1
-(Fix) Possible (rare) crash when listing runs
-(Model) Bike+rider mass is estimated during a climb (Training mode)
-(UI) Detect low PM battery level

2.5.0
-(UI) CSV files now listed per day
-(Phones) Android 10 supported
-(Phones) Android 4.3 and older not supported anymore (eg: Xperia Active st17i)
-(Fix) Tempe Garmin deconnections caused temperature issues
-(Fix) Virtual elevation on time trial mode

2.4.8
-(Fix) Regression introduced in 2.4.2 with devices badly detected by ANT+ dongles
2.4.7
-(Model) Data from WeatherMeter device is used in priority for relative humidity
-(Model) Add option to get temperature from the WeatherMeter anemometer
-(UI) Add PM battery voltage on the screen
-(Fix) Data from WM sensors were not shown on the Device/ANT+/BLE line
-(Fix) "-0" instead of "0" indicated on the Power field when power is null
2.4.6
-(Crash) Regression introduced in 2.4.5 fixed
-(Output) Online aero tool http://MyCdA.app can now read CdaCrr .fit files
2.4.5
-(Model) Calibration algorithm improved
-(Output) Write vertical vibration into SMO2% FIT field
2.4.4
-(Settings) Add default relative humidity into the settings
-(Output) Estimate and monitor gearing (big chainring only)
-(Output) Change format of the Lap.csv file for training mode
-(Format) Fit SDK updated to 20.88.00
2.4.3
-(Output) Airspeed added into the SMO2 field of FIT file
-(Feature) Fix wind forecast screen (3 hours period instead of 1 hour, though)
2.4.2
-(Output) GPS Lat/Lon added to Raw.csv file
-(Feature) Outliers detection (Grubb's test) for CdA of a run (purple flag is shown, suggesting to delete the lap)
-(Fix) Typo in the line Mean in the Lap.csv file
-(Fix) Comment with micro was not working on Android>=6.0 (needed authorization)
2.4.0
-(Mode) New training mode (add training metrics on lap/run)
-(Mode) Automatic segment mode (live CdA during a ride) is not a premium feature anymore
-(Mode) Home trainer mode is suppressed, but try to guess if home trainer is used
-(Feature) Add wind direction/current location to Wind forecast menu + fix a bug
-(Feature) Ask for powermeter manual calibration each time the zeroing strategy is changed
-(Model) Try to calibrate the different elevations by the more accurate one
-(Model) Several modes (TimeTrial, Segment, Criterium, Training) can now be used with GPS altitude data
-(Model) Estimate total mass (rider+bike) during long and steep enough climbs (training mode only)
-(Model) Try to estimate anemometer calibration factor after each lap/run
-(Model) For crank based PM, lap is now cancelled only if pedalling less than 90% of the time
-(Format) Fit file format replaces iBike one
-(Fix) Useless laps added during velodrome sessions when bike is stopped
-(Fix) Distance overestimated if datadrops happened
-(Fix) Try to improve ANT+ speed sensor reconnection
-(Fix) GSM location fixed
-(Fix) Turn off Bluetooth when the Weathermeter is disconnected in order to improve reconnection
-(Fix) Improve speed spikes fix and add a sonore warning
-(Fix) Averages for power or wind could be wrong
-(Fix) Graphics crashed with old Android versions
-(Fix) Bike stops may not be detected correctly with ANT+ speed sensor
-(Fix) Error in watts gain/loss when the Weathermeter was activated
-(UI) Option to record data from two powermeters
-(UI) Setting to disable beep warning for ANT+ data drops
-(UI) Search of ANT+ devices is not automatic anymore
-(UI) Add three more configurable fields (swipe down current fields to make them appear)
-(UI) Add new fields plus lap, run and ride averages for some of them (speed, power, ...)

4 comments:

Anonymous said...

Hi. Was using the 4.0.1 app downloaded from play with the purchased key. And was crashing or restarted on Samsung Android v14 every time l pressed start. Running with WM. Uninstalled this version and download 4.1.0 from above. This won't open on my phone with a message stating it has a bug. Any tips please. Cheers Sean

bugno said...
This comment has been removed by the author.
bugno said...

Indeed, Android 14 is not supported for the moment. Only Android 13 or before.

bugno said...

If you not have an other phone, I can refund your licence purchase.