Apple released iOS 10.3.1 Monday. The patch notes are sparse, saying only, “iOS 10.3.1 includes bug fixes and improves the security of your iPhone or iPad.” The company has not yet published the security release notes, but this update is most likely addresses issues that cropped up since the release of iOS 10.3 last week.
The update was a 30.2MB download as an over-the-air (OTA) update on iPhone 7. You can also download iOS 10.3.1 through iTunes, where it is much larger.
For those who plunge ahead with updates, please drop your experiences into the comments below for those smart enough to let us go first. My own update on iPhone 7 is progressing smoothly as I write this.