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By Coldflower Design Corp.

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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:

Due to the CPU intensive nature of analyzing real time audio, the iPhone 5 or higher is recommended for devices running iOS 7. If you are running iOS 6 or earlier, you will be prompted to download a legacy version of Kello, optimized for use with the iPhone 4, 4S, and 5.

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.

What's New in Version 2.43

This update increases the sensitivity of the signal amplification to better accommodate watches with plastic escapements, like those found in the Swatch Sistem51, Tissot Powermatic, and Hamilton Pan Europ Auto. Optimal placement of the microphone near the escapement is still critical to achieving a clean signal on these watches. Please feel welcome to get in touch, with the make and model of your watch, at, for guidance on how best to position the microphone.

The rate averaging period has also been increased in this update to provide more stable results. If you use Kello to make changes to the rate of timekeeping of a timepiece, pause and restart analysis between adjustments to ensure the accuracy of results.

iPhone Screenshot

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Customer Reviews

Not good

15 minutes in a quiet room, two different microphones and no results. Give me my money back!

View In iTunes
  • $11.99
  • Category: Utilities
  • Updated:
  • Version: 2.43
  • Size: 1.3 MB
  • Language: English
  • Seller:

Compatibility: Requires iOS 7.0 or later. Compatible with iPhone, iPad, and iPod touch.

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