watchOS 4 is an operating system that was designed, developed by Apple in 2017, and was preinstalled on the new Apple Watches and as an update through the iPhone for the previous series. The system has been released on September 19, 2017, and gets the last update (4.3.2) on July 9, 2018, and later has been replaced by a newer version of watchOS 5.
watchOS 4 features a proactive Siri watch face, personalized activity coaching, and an entirely new music experience. It also introduces GymKit, a technology platform to connect workouts with cardio equipment.
Today watchOS 4 is 5 years old!
watchOS 4 General Information
| Released | September 19, 2017 |
| Original Price | Free |
| System Requirements | Apple Watch Apple Watch Series 1 Apple Watch Series 2 Apple Watch Series 3 iPhone 5s or later iOS 11 or later |
| Distribution | Trough paired iPhone |
Versions
| Versions | Build | Release Date |
| watchOS 4.0 | 15R372 | September 19, 2017 |
| watchOS 4.1 | 15R846 | October 31, 2017 |
| watchOS 4.2 | 15S102 | December 5, 2017 |
| watchOS 4.2.2 | 15S542 | January 23, 2018 |
| watchOS 4.2.3 | 15S600b | February 19, 2018 |
| watchOS 4.3 | 15T212 | March 29, 2018 |
| watchOS 4.3.1 | 15T567 | May 29, 2018 |
| watchOS 4.3.2 | 15U70 | July 9, 2018 |
