keuwlsoft Apps

Function Generator 1.2
keuwlsoft
Dual channel function / waveform / signalgenerator for the speaker / headphone audio output.No Ads, No Permissions, No In App Purchasing, No LimitedFeatures. Full Version.Output is 16 bit for each left and right channels and at44.1kHz. Output will depend on your device hardware. Some devicehardware may may filter out the DC bias and low frequency signals.At high frequencies, the waveforms will be distorted due to limitednumber of samples for each waveform (for example at 4.41kHz, a sinewaveform will be approximated by only 10 points). Therefore this isfor fun/educational use, for critical applications use a realcalibrated function generator.Left and Right audio channels can be assigned to either channel1 or channel 2.Sine, Square & Triangular waveforms.Frequency range from 1 mHz up to 22 kHz.Amplitude as percentage 0-100%.Set duty for square waveforms or skew triangular waveforms to getsaw waveforms.Offset the phase of waveforms.Sweep frequency or amplitude (Single, Repeat & Bouncemodes).Amplitude Modulation (AM).Frequency Modulation (FM).Burst mode for a specific number of waveforms (1-10000).White noise & pink noise Generator. Pink (1/f) noise falls ofat ~3dB per octave between 43 Hz and 44 kHz.Memory slots to save & recall channel configuration.Select values with spring slider or number pad.More detailed explanation available on website
Guitar Tuner 1.41
keuwlsoft
Straightforward guitar tuner. Single screenapp that starts in auto tune mode. Simply run the app, hit a stringand start tuning your guitar. Tune into the orange region for agood results or green for perfection.This app uses your microphone to detect the string being played andindicate if you should tune up or down.Pitch pipe function also included.The standard EADGBE guitar (not implemented for very small screendevices) indicates current note being played or allows fast noteselection in manual mode.Tuning range from 30 Hz (B0) to 4186Hz (C8), so can also be used totune other stringed instruments.
Audio Frequency Counter 1.01
keuwlsoft
Frequency counter based on the microphoneinput. Counts when the input rises or falls past a set level andconverts into into frequency or a time period. FOR INDICATION ONLY.Results depend on your device and its hardware. If you just want toknow the frequency of a sound with harmonics (e.g. mucialinstrument), a FFT based app such as keuwlsofts spectrum analyseror guitar tuner (both free) will be better. This app can providemore accurate frequency measurement for single frequency inputsignals. Features include:Display of triggered event count and frequency or timeperiod.Graph of input signal, 2.5 ms/div up to 640 ms/div.Gate time of 0.1s, 1s, 10s or 100s.Gain from x1 to x1000.Trigger on rise or fall.AC or DC coupling.Set a noise level so new event is not triggered until the signalhas first passed this level.More details can be found on the website.
Sand Timer 1.2
keuwlsoft
Hourglass timer with great graphics, no ads& no permissions.Great for board games, as a kitchen timer, or for telling thekids how long until bedtime.Operate up to 8 sand timers simultaneously (each one is coloreddifferently and selected at left of screen).Accelerometer used - turning upside down will reverse the timeand reset the timer (option to turn this off).Set the countdown time anywhere from 1 second up to 83 days.Change timer names. Changes will be stored for next time app isrun.Notifications will be shown if the timer finishes when the appis not open.
USB Host Test 1.1
keuwlsoft
Tests your device USB Host capability by listing the USB devicesattached.Simply run the app, plug in your USB device(s) and clickfind.Copy results to clipboard ready for pasting into othersoftware.Not all devices have USB Host capability. For USB devices to bedetected we need:Android 3.1 or newer (USB Host API support)Device that has USB hardware.Compatible Kernel that links the hardware to the API. (Rooting orchanging kernel can often solve USB connectivity issues, but onlyattempt if you know what you're doing).USB OTG connection.Sufficient power on the USB bus.If USB devices are detected, details reported include:Device Serial NumberVendor IDProduct IDManufacturer String DescriptorProduct String DescriptorClass, Subclass and ProtocolUSB VersionMax PowerNumber of ConfigurationsNumber of InterfacesInterface and Endpoint InfoNote the amount of info shown will depend on the USB device andthe amount of access allowed.
Gauss Meter 1.01
keuwlsoft
This app uses the magnetic field sensor onyour device to measure magnetic flux density (B) in Gauss or Tesla.FOR INDICATION ONLY. Results depend on your device and itshardware. Your device must have a Magnetic Field Sensor for thisapp to function. Features include:Analogue dial to show current reading.Averaging.Maximum and minimum values.Gauss or Tesla units.4 time constant options. 3 Refresh speeds.Graph – Shows the time depedence of the magnetic field.CompassFerrous metal detector – sound frequency will change with gausslevel.Autoscale or manual (pinch & pan) Y-Axis.Calibrate option – If you have a calibrated gauss meter or knownmagnetic source, you can use this option to calibrate the meter.(However app is still for Indication Only).More details can be found on the website.
Harmonicity Meter 1.11
keuwlsoft
Measure the Harmonic to Noise Ratio(Harmonicity) from your microphone.Harmonicity is a measure of the sound energy in the harmonicsrelative to the rest of the spectrum.Harmocity varies with age, gender & which vowel you pronounce.Higher harmonicity values indicate a purer sound. Whilst lowerjitter and shimmer values indicate a purer sound.This meter is supposed to be used with a continuous consistentsound, e.g. Pronoucing a vowel, or a tone from aspeaker/instrument. Rapidly changing tone/sound will givenonsensical output.FOR INDICATION ONLY. Harmonicity will vary depending on how closethe source is to the microphone. Microphone sensitivity varies withfrequency and from device to device. Even amoungst scientificliterature, it is difficult to find consistency in absolutereported values.Jitter is a measure of the frequency variation of the sound. Therelative jitter is shown as a %.Shimmer is a measure of the amplitude variation of the sound. Therelative shimmer is shown as a %.Autodetects sound – App will only start measuring when a sound isdetected.Averaging - After 0.7s, the app will start averaging theHarmonicity, Jitter, Shimmer and freqency values. This willcontinue until the sound is stopped at which point the last 0.7s ofdata is removed from the averaged values.Musical Note – The current detected frequency is converted into anote based on western 12 tone equal temperament. Use to tune yourguitar or other instrument if you wish.Pause button – Useful if in a noisy environment and measurementdoesn't auto stop.FFT Spectrum – Autoscaling Sound Intensity between 0 and 2kHz.Range: 100 Hz to 2 kHz fundamental harmonic frequencydetection.Internet Permission is for link to website with more info/userguide for app.Technical bit:The fast fourier transform (size 8192) is performed on the last0.74s of data to produce a frequency spectrum (0 to 5.5 kHz with1.35Hz resolution). This frequency spectrum is windowed between 100and 4 kHz with linear fall offs to zero at 50 and 5 kHz. Thefundamental frequency is determined from polynomial fitting topeaks. The harmonic energy is determined from the sum of the FFTsignal at the harmonic freuquency plus 8 Hz either side. The noiseis the sum of the rest of the FFT. The ratio of harmonic to noiseenergy is the Harmoicity and is displayed in decibels.More technical details can be found on the website.
Metronome 1.1
keuwlsoft
Metronome with no ads & no permissions.♩ Beats per Minute (BPM) from 10 up to 310 in 0.1 BPMintervals.♩ Moving pendulum with motion blur effects.♩ Accelerando slider for gradual speeding up/slowing down. (0.1 to10 BPM/bar)♩ Beats highlighted on musical staff as they are played. Accent ormute any of the beats by tapping above/below note.♩ Select up to 12 Beats per bar. Set beat value to half note,quarter, eighth or sixteenth.♩ Three different sound effects to choose from.♩ Select from 0 to 9 sub beat divisions.
Spirit Level 2.01
keuwlsoft
Spirit Level. No Permissions Required. Free& No Ads.• Bulls eye level with roll & pitch gauges screen• Horizontal and vertical bubble level and angle gaugescreen.• Calibration feature to correct for accelerometer misalignment& different axis sensitivities.For best results touch CAL and calibrate first. The Spirit Levelis only as good as your accelerometer. For indication only. Don'tdamage your tablet or phone, use a real spirit level whenappropriate.• Pause button to hold the current reading.• Zero and reset button to make measuring angles easier.• Option to auto select screen based on inclination.That's it. Enjoy.
Light Meter 1.2
keuwlsoft
This app uses the light sensor to measureilluminance in lumens per square meter (lx) or lumens per squarefoot (foot candles). FOR INDICATION ONLY. Results depend on yourdevice and its hardware (Not every device has a light sensor andquality of the sensors varies massively). Features include:Analogue dial to show current reading.Averaging.Maximum and minimum values.lx or ft-c units.4 time constant options. 3 Refresh speeds.Graph – Shows the time depedence of the light.Autoscale or manual (pinch & pan) Y-Axis.Calibrate option – If you have a calibrated light meter or knownlight source, you can use this option to calibrate the meter.(However app is still for Indication Only).More details can be found on the website.
Bluetooth Electronics 1.1
keuwlsoft
Control your electronic project with anAndroid device. This app communicates using Bluetooth to an HC-06or HC-05 Bluetooth module in your project. This app comes with alibrary containing 10 Bluetooth examples for Arduino. It can alsobe used with Raspberry Pi or any other rapid prototyping system inwhich you have included a suitable Bluetooth module to yourproject.Ideal for learning electronics in a fun way.Ideal for rapid prototyping a new idea.Ideal for exhibiting your project.Some electronics skills required. Requires an Android devicewith Bluetooth capability enabled. Does NOT work with Bluetooth LowEnergy.Large selection of controls available including buttons,switches, sliders, pads, lights, gauges, terminals, accelerometersand graphs. Drag and drop them onto the panel grid. Then edit theirproperties.20 customisable panels available. Import/Export panels.Discover, Pair and connect to Bluetooth devices. Then click Runto use the panel.Library of 10 Arduino Examples to get you started:LED Brightness - PWM with a Slider controlRC Car demo – Basic Button controlsPersistence of Vision – Text controlRepeater Demo – Send and Receive TerminalsUltrasonic Distance Sensor - Light IndicatorMEGA Monitor – GraphsUNO Monitor – More graphsTemperature and Humidity – Temperature GaugeConfigure HC-06 Demo – In-case you want to change Baud rateMotor Control Demo – Accelerometer and pad controlsFinally, You undertake any electronic project at your own risk.Please be careful. Consider what is going to happen to your projectif the Bluetooth connection is lost, or the Android devicecrashes.
Compass 1.01
keuwlsoft
Uses the Magnetic Field Sensor to convert yourdevice into a Compass. Does not need to be level. Magnetic Northand True North Needles. Free & No Ads.Location is required to determine the magnetic declination - thedifference between magnetic north and true north (Hence theACCESS_FINE_LOCATION Permission). If GPS/Network location is notavailable or turned off, then the location can still be enteredmanually.Normally a compass needs to be level to get the correct reading,but this app uses the accelerometer reading to convert the magneticfield reading back to the horizontal plane. If you would prefer itto act like a real compass (which requires being level for acorrect reading), in Settings > Mag North, select the magneticnorth to point to the maximum field in the plane of the device.Also:• Bull's eye Bubble in Compass to show how level it is.• Roll and Pitch Gauges.• Calibrate Bubble Level Option.• Heading in Azimuth or Quadrant Notation.• Magnetic Field Strength and Inclination.• Rotatable dial with orienting lines.• GPS/Network Location – Latitude, Longitude and Elevation (GPS canconsume a lot of battery, therefore it is only measured continuallywhen the location display is shown. Otherwise just one reading istaken from which the magnetic declination is determined).Your device must have a Magnetic Field Sensor for this app towork. Magnetic field direction can be affected by nearbyferromagnetic material - Therefore move into a clear area andremove any metallic casing that might interfere with the sensor.Some sensors can become magnetized or gain an offset resulting infalse readings – rotating the device around each of the three axiscan sometimes help. Results depend on quality of magnetic sensor,so use for indication only.
Accelerometer Meter 1.32
keuwlsoft
View or log output from your accelerometersensor. The app has six screens to choose from:MeterThis show the output from the accelerometer and minimum and maximumvales recorded.GraphPlots the accelerometer output over time. Option to save data.SpectrumShows the frequency spectrum of the recent accelerometer data. Useto find resonant frequency's.LightConverts the accelerometer sensor output into a colour. Wave thedevice around and the colour will change.MusicThis is a musical instrument based on the accelerometer sensor.Orientation selects the note and pitch the volume. It is based on a5 equal temperament notes per octave scale so that the music willstill sound reasonable even if played badly.InfoThis screen provides info on your sensor, such as vendor, version,resolution and range. It also shows info for other sensors on yourdevice.Free & No Ads. No time limits, no restricted features etc,this is the full version.Write external storage permission so that you can save the datain graph or spectrum modes.
Ruler 1.02
keuwlsoft
A simple, but very handy on screen ruler.NoPermissions, Free & No Ads.Automatically sizes to most screens. However, check scalingwitha normal ruler on first use. If it is not correct, touch CALandstretch the ruler to the correct size.• Centimeters and inches.• Measure length between two markers.• Copy to clipboard.
GPS Waypoint Finder 1.00
keuwlsoft
Uses the GPS sensor, Magnetic Field Sensor andAccelerometer to determine the distance and direction to a GPSwaypoint. Does not need to be held level. Free & No Ads.Normally a compass needs to be level to get the correct reading,but this app uses the accelerometer reading to convert the magneticfield reading back to the horizontal plane.In addition to the direction and distance to the waypoint, acompass ring shows the current heading. North points to True North(i.e. The direction is corrected for the magnetic declination - thedifference between magnetic north and true north).The GPS reading and the time since that reading is shown at thebottom of the screen.Use for geocaching, finding your car, hotel, or otherlocations.• Store up to 500 waypoints.• Imperial or Metric units.• Import and Export waypoints as GPX files.Arrow colour changes to green at less than 30m and blue at lessthan 10m to make it easier for littler ones to identify thatthey've reached the waypoint.Whilst walking, look where your going, not at the app or youmight trip! The app tells you the direction of your destination,not how to get there.Only as good as the sensors in your device. Use for IndicationOnly.
Car Challenge 1.00
keuwlsoft
Guide your car to the end of each trackwithoutcrashing. Good timing and memory are required to completeeachlevel.• 25 tracks• 5 Different Cars• Designed to be played in the hard difficulty setting(nocrashing allowed), however easy and medium difficulty (carscantake some damage) are also available.No Ads & No Permissions.
Wifi Analyser 1.04
keuwlsoft
Monitor strength of nearby wifi networks. Useto find a good location for your wifi hub. Or use to identify achannel with little overlap with neighbouring networks.App has 4 screens:• Gauge – shows the signal strength of the currently connectedwifi network. Also shows maximum, minimum and average values. Graphwith auto-scale & speed options.• Channel – shows how the wifi networks are spread across thechannels and overlap each other.• Graph – shows how the signal strength of all nearby networksvary with time. Auto-scale & speed options. Select whichnetworks to display.• List – Contains basic information for all the detectednetworks: name, mac address, frequency, channel, encryption typeand signal strength.Free & No Ads. For indication only. Enjoy.
Protractor 1.02
keuwlsoft
Protractor for measuring Angles. Free & NoAds.• Camera view with Pause button.• Measure angle between two markers.• Horizontal and vertical plumb lines (Tap to snap nearest markerto line, double tap to track, tap again to release).• CAL button to calibrate Accelerometer if plumb lines areout.• Copy angle in degrees and radians to clipboard.
Stopwatch 1.1
keuwlsoft
Stopwatch with great graphics, no ads &nopermissions.Operate up to 8 stopwatches simultaneously (each one iscoloureddifferently and selected at top of screen).Log up to 100 Lap or Split times for each stopwatch.Pressing Split before starting stopwatch will change to Lapmode& visa versa.Stopwatch settings and times are stored for the next time theappis run, so it will appear that the stopwatch has beenrunningcontinuously in-between.
Multi Piano 1.2
keuwlsoft
Play up to 4 pianos simultaneously ononedevice. Choose one of 8 arrangements to suit your needs,whetherplaying alone or with friends. Notes played are highlightedon theother pianos to make teaching a new tune easy. Slide the barbelowthe piano to access higher or lower pitch notes.Features:Multitouch8 Piano arrangements with up to 4 pianos to choose from.Adjustable piano key width.Highlights note played on other pianos to make teaching easy.Pianos keys range from C1 to C8.No Ads & Free.(Note that C1 to C3 will be quiet on most deviceonboardspeakers, play through headphones or a sound system forbettersound quality)
Keuwl Music Pad 1.3
keuwlsoft
What if there was more than 12 notes inanoctave? or less? Create new instruments with up to 53equaltempered notes per octave and explore the sounds ofsuchinstruments with this app. This music pad also allows you toslideup and down the particle beams to create cool sounds byincreasingthe pitch smoothly betwen octaves without changing thenote. Thesefeatures combined enable you to create new unique soundsthat canteasily be replicated on other instruments.Notes range from C1 to C8 (play across 7 octaves).Show note ratio (2:3 perfect fifth, 3:4 perfect fourthetc.)option for easy playing in harmony.Snap to octave option for precise note selection.Four different sounds.Free, No Ads, Full version.
Geo Protractor 1.01
keuwlsoft
Measure angles between two points on the geosphere with the camera and augmented reality. Free & NoAds.Device orientation is obtained with the accelerometer andgyroscope, or with the accelerometer and magnetic field sensor.Each method has advantages and disadvantages and can be selectedwith the gyro or magnet buttons (only if your device has thenecessary sensors detected).A sphere with azimuth and angle of elevation lines is shownoverlaying the camera view.Two positions can be set putting markers onto the view. The anglerequired to rotate from one to the other is shown, as is thedifference in azimuth and angle of elevation between the twopoints.For Indication Only. Note that in gyroscope mode, the azimuth willdrift slowly. In magnetic mode, the Earths magnetic field can bedistorted by nearby metallic objects and give incorrect azimuthreadings. For Indication Only.
Pulse Echo Sonar Meter 1.01
keuwlsoft
Uses the audio autput to generate sound pulsesand then detects the echo on the microphone. The echo signal can bevisulised in a map, Fourier transformed or just as the time-serieswaveform. Great for investigating/demonstrating acousticsprinciples. Free & No Ads.RECORD_AUDIO Permission to use microphone to detect the echo.WRITE_EXTERNAL_STORAGE Permission is so that data can besaved.Features/Specifications:• Sampling frequency 44.1 kHz.• Sampling duration 0.001 s to 5 s.• Single / Continuous modes.• Save Data in CSV files.• Pulse Generation:• Single/Train/Chirp.• Square/Sine waveforms.• Tukey/Hanning Envelopes.• Pulse frequency 20 Hz to 22.05 kHz.• Pulse duration up to 1 s.• MAP – Visualise the echo. Colour or Black and White. Pixel valuefrom RMS or absolute value. New line for each echo trace. Movedevice whilst pulse-echoing to generate a map.• Fast Fourier Transform (FFT) of 8192 data points to determinefrequency content between echo detect lines.• Peak frequency detection• FFT AveragingFor Indication Only. Use Ear Protection if required. Due to thelimits of the typical microphone dB range on most devices, distantecho signal are likely to be too weak to detect clearly unlessextra amplification or a strong echo is present.For fun/educational/research use. This is not ultrasound and NOTsuitable for any medical imaging. This app can create annoying loudsounds, so use ear protection if required.
LED Banner Scroller 1.01
keuwlsoft
Display scrolling messages. Sendencouragement, display notices, get peoples attention, and morewith this led banner scroller. Includes an experimental multiscreen option for displaying the message over multiplescreens.Features:• Up to 6 lines of text.• Portrait or Landscape banner.• Mirror option for when banner is to be viewed through amirror.• Left, right, up, down or static scroll options.• Vary scroll speed.• Choose text & background colors.• Alter LED grid size.• Auto or manual size text.• Left, center or right text justification options.• 20 Memory slots to store messages.• Create messages in any language.• Multi Screen (uses RECORD_AUDIO permission & might not workon all devices). Uses audio communication to transfer scroll infoto nearby devices to create a longer scroll comprising multiplescreens. Set one device as the Master, and the others as Minions.Hold the speaker near the microphone of the receiving device(s) forbest results.Free & No Ads. Enjoy.
Spectrum Analyser 1.31
keuwlsoft
Free audio spectrum analyser for yourmicrophone.No ads. Full version.64 up to 8192 frequency divisions (128 to 16384 FFT size).22 kHz spectrum range (can reduce down to 1 kHz for higherresolution).FFT Windowing (Bartlett, Blackman, Flat Top, Hanning, Hamming,Tukey, Welch, or none)Auto-scale or pinch to zoom, drag to pan.Linear or logarithmic scales.Peak frequency detection (polynomial fit).Averaging, Min and Max.Save CSV data files (uses Write External Storage Permission).Free or snap to peak cursor.Octave Bands - Full, half, third, sixth, ninth or twelfthbands.Weighting – A, C or None (A weighting filters the high and lowfrequencies according to how the ear perceives soundloudness).Musical note indicator (green if within 5 cents, orange if within10 cents).Auto-scaling microphone input trace.For best response on slower devices, keep the FFT size low.More detailed explanation available on website
Keuwl Guitar Tuner 1.11
keuwlsoft
Keuwl Guitar Tuner uses the microphone to autodetect the pitch of the note being played. The 3 dials will rotateto show the note being played. The middle dial shows the pitch ornote name. The inner dial shows the octave. The outer dial willshow if the note is flat or sharp - The orange region is within 10cents for good tuning, the green is within 5 cents for moreaccurate tuning.Keuwl Guitar Tuner is free. No ads. No trial version. No timelimits. No restricted features. The only permission is formicrophone access. This is the full version!Whilst optimised as a guitar tuner, this app can be used for tuningmany other musical instruments. Frequency detection from B0 (30 Hz)up to C8 (4186 Hz).In addition to 12 Tone Equal Temperament(12-TET), choose from justintonation, Pythagorean, 5-limit, 7-limit, quarter comma meantoneand N-Tone equal temperament tuning. For N-Tone ET, N can rangefrom 5 to 52.Shift feature for those that don’t want A to be 440 Hz or if youneed to tune to accompany your out of tune friends. Get them toplay a note, hit the shift key, and rotate the dial to what theythought they played. Hit the shift key again and then tune asnormal. Remember to hit reset to get back to original settings atany time.Pitch Pipe also included.
Flashlight 1.10
keuwlsoft
Flashlight (aka Torch), Free, No Ads. Just agreat app with some cool features....Torch Mode – Turn the camera LED on and off. If no Camera LED isdetected, the torch option is not available. (uses FLASHLIGHT &CAMERA Permissions).Screen Mode - Use the display as a light - Swipe up/down to changecolor, left/right for brightness or diagonally forcolor/grey.Music Mode – Lights and graphics that move in response to sounddetected on the microphone. (uses RECORD_AUDIO permission).Accelerometer Mode – Color will change with orientation of device.Wave about at a music festival for a cool effect.Hazard Mode – In trouble, or just want some cool flashing lights.Change speed, color and blink pattern.Widget - (Navigate to widgets, hold on icon for 4s & place onhome screen). Widget turns LED on and Off (or loads the app ifthere is no LED).Please Note:1) Flashing lights can cause epileptic fits in some people, so useflashing features with caution.2) These lights do not have reflective properties - car/bike lightsare a combination of reflector and light – therefore use a properlight designed for its application when possible.3) Don't shine the bright torch in eyes - it hurts.Enjoy!
SPL Meter 1.02
keuwlsoft
Sound Pressure Level Meter. This app uses themicrophone to detect sound and convert it into an SPL value. FORINDICATION ONLY. Results depend on your device and its hardware.The range between the noise floor and saturation may be only 20 dBon the worst devices, but could exceed 100 dB on the bestdevices.Features of this SPL meter include:Analogue Dial with Max and Min indicators.Weighting – A, C or None . (A weighting filters the high and lowfrequencies according to how the ear perceives sound loudness).Results are in dB, dBA or dBC depending on weighting.Averaging of SPL, Clear and Pause buttons.Octaves and third octaves - Frequency spectrum of the sound.Graph – Shows the time depedence of the sound.Autoscale or manual (pinch & pan) Y-Axis.Relative button – if looking for differences, tapping REL willremove the current averaged value from the reading.Calibrate option – If you have a calibrated SPL meter or knownloudness source, you can use this option to calibrate the meter.(However its still for Indication Only).More technical details can be found on the website.