Kello at App Store analyse

App power index: 385 (based on ranks around App Stores today)
Utilities Education
Developer: Coldflower Design Corp.
Price: 0 free
Current version: 2.49, last update: 1 year ago
First release : 11 Jul 2010
App size: 1.18 Mb
4.0 ( 3920 ratings )
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Estimation application downloads and cost

> 8.47k
Monthly downloads
~ $ 3.47k
Estimation App Cost


Kello analyzes the precision of mechanical watches against the iOS system clock using a microphone.


How Kello works:

All mechanically regulated watches are designed to start and stop 1000s of times every hour. A portion of the energy used during this starting and stopping motion is released as acoustic energy, resulting in an audible "tick-tock" sound. The regularity of this sound can be measured against the more precise, internal time-signal of iOS devices, such as the iPhone, and the resulting difference in timekeeping is displayed by Kello.


Supported Watch Frequencies:

Kello can automatically determine the frequency of the watch being measured based on eight of the most common frequencies used in mechanical watches. These frequencies are standard among low-, middle- and high-grade mechanical timepieces and will accommodate the vast majority of mechanical watches produced in the past 100 years. The following frequencies are supported:

* 14,400 bph
* 16,200 bph
* 18,000 bph
* 19,800 bph
* 21,600 bph
* 25,200 bph
* 28,800 bph
* 36,000 bph


Recommended hardware:

Kello works best with an external microphone that has an excellent frequency response between 10,000 and 20,000 Hz.


How to know if your watch is mechanically regulated:

There are four simple ways to determine if your watch is mechanical and can be used with Kello.

1. Look at the text on your timepiece. If the word "quartz" is featured anywhere on the watch, your watch is not mechanical. If the words "automatic" or "shock-proof" are written anywhere on the watch, there is a very high chance that your watch is mechanical and its precision can be measured by Kello.

2. If your watch has a hand that indicates the seconds, observe how frequently it moves. If the hand moves only once every second, it is very likely that your watch is not mechanical. If this hand moves several times per second or appears to sweep along in a smooth, continuous motion, your watch is most likely mechanical and its precision can be measured by Kello.

3. Turn the crown, that is used to set the hands of the watch, while it is pressed fully in. If the crown turns smoothly, your watch is not mechanical. If you can hear a ratcheting sound as you turn the crown, your watch is most likely mechanical and its precision can be measured by Kello.

4. Place the watch close to your ear and listen. If you hear a noise approximately once every second, it is unlikely that your watch is mechanical. If you hear a constant ticking noise, your watch is very likely a mechanical watch and its precision can be measured by Kello.
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# Term Store county Place Priority
1 clockmaster 15 ⭐️⭐️⭐️⭐️
2 clock master 15 ⭐️⭐️⭐️⭐️
Available in countries
Country Price
Canada 9.99 CAD
China 68 CNY
France 9.99 EUR
Germany 9.99 EUR
Italy 9.99 EUR
Netherlands 9.99 EUR
Portugal 9.99 EUR
Spain 9.99 EUR
Poland 10.99 EUR
UK 9.99 GBP
India 999 INR
Japan 1500 JPY
Korea, Republic Of 14000 KRW
Poland 49.99 PLN
Russia 899 RUB
Turkey 299.99 TRY
USA 9.99 USD
Korea, Republic Of 10.99 USD
Ukraine 11.99 USD
Available for devices
iPhone4, iPad2Wifi, iPad23G, iPhone4S, iPadThirdGen, iPadThirdGen4G, iPhone5, iPodTouchFifthGen, iPadFourthGen, iPadFourthGen4G, iPadMini, iPadMini4G, iPhone5c, iPhone5s, iPadAir, iPadAirCellular, iPadMiniRetina, iPadMiniRetinaCellular, iPhone6, iPhone6Plus, iPadAir2, iPadAir2Cellular, iPadMini3, iPadMini3Cellular, iPodTouchSixthGen, iPhone6s, iPhone6sPlus, iPadMini4, iPadMini4Cellular, iPadPro, iPadProCellular, iPadPro97, iPadPro97Cellular, iPhoneSE, iPhone7, iPhone7Plus, iPad611, iPad612, iPad71, iPad72, iPad73, iPad74, iPhone8, iPhone8Plus, iPhoneX, iPad75, iPad76, iPhoneXS, iPhoneXSMax, iPhoneXR, iPad812, iPad834, iPad856, iPad878, iPadMini5, iPadMini5Cellular, iPadAir3, iPadAir3Cellular, iPodTouchSeventhGen, iPhone11, iPhone11Pro, iPadSeventhGen, iPadSeventhGenCellular, iPhone11ProMax, iPhoneSESecondGen, iPadProSecondGen, iPadProSecondGenCellular, iPadProFourthGen, iPadProFourthGenCellular,