Chronographer

Chronographer helps you track the long-term accuracy of your mechanical watches.
Use Chronographer to periodically collect data points comparing your watch’s time to the current correct time. Chronographer stores this information and uses it to create graphs tracking each watch’s offset (the difference from the correct time) and deviation (how many seconds it gains or loses per day). Graphs show individual data points and best-fit trend lines over timespans ranging from a week to a year. Chronographer also calculates detailed metrics about each watch’s accuracy.
Chronographer can store information about your whole watch collection. Give each watch a name and, optionally, a longer description. You can select a picture from your Photos library and add additional notes, such as the watch’s specifications, purchase details, and service history. All information can be stored in iCloud and automatically synchronized between your devices.
You can use Chronographer to track positional variation. Whenever you record a data point, you can include the position (dial up, crown up, etc.) that the watch was stored in. Then, you can restrict the graphs and metrics to specific positions and compare the results.
For best results, collect a data point for each of your watches every day or two.
Chronographer includes a large digital clock to help when you set your watches.
You can export your watch data to local storage or to iCloud Drive. This is useful for backups and to share your data.
For more information, including a detailed user’s guide, see https://www.rmfrance.net/chronographer