Watch Spring 4+

Watch Spring measures the accuracy of your mechanical watch. Watch Spring's watch accuracy checking is designed to work with manual and automatic mechanical watches. Your watch’s accuracy is measured by comparing the time on your watch with the time on your iOS device. Over time, the accuracy data allows Watch Spring to:

- Visually show how accurate your watch is
- Estimate the average seconds per day accuracy drift
- See the accuracy of your watch over the long term; useful for spotting anomalies or when a service is due
- Visualise how often you are wearing each of your watches
- Keep track of your watch collection in one place

Other features include:
- Import and export your watch accuracy history
- Export charts and graphs for sharing with others
- Notifications to remind you to check your watch’s accuracy
- Clock with seconds hand for setting the time on your watch
- Intuitive, simple to use, iOS native app

To check the accuracy of your watch is simple. Watch Spring shows a clock at a fixed time a few seconds in the future. Hold your finger on the clock. When the time on your own watch matches the time shown on the Watch Spring clock then you lift your finger and Watch Spring does the rest.

** Important note **
Although it is possible to take accuracy readings every few seconds, it is important that you keep at least a couple of hours between accuracy checks. Very short intervals between time checks will lead to some very misleading estimates. This is a side effect of the 0.1 - 0.3 second variance of the manual process for doing the accuracy check.

Another tip when swapping watches over on your wrist is to take an accuracy check of the watch you are taking off right before you then take an accuracy check of the watch you are putting on. This allows Watch Spring to accurately track how long you have been wearing each watch.

On a personal note, I use Watch Spring every single day and have done so since January 2022 when I started creating this app. I use Watch Spring to check the accuracy of the watch I am wearing every morning (the notification reminds me if I forget). I also use the wear statistics to make sure I am giving all my watches decent wrist time. I have also used the wear history statistics to help me decide which watch to sell in order to make room for a new one. The Watch Spring generated charts have also been handy to explain accuracy problems as part of warranty claims with watch dealers! Pretty much every feature in Watch Spring has been added because I have needed it for some reason or other. I hope you find it as useful as I do.