The Apple Watch had its first software update this week, and it did include some minor updates to the health tracking features. In addition, reports have surfaced of additional health features Apple might be planning to add as the company's June 8th Worldwide Developer Conference approaches.

Although the exact details are elusive, yesterday's Apple Watch software update included changes to the way the watch tracks standing activities, changes to how it tracks calories for indoor cycling and rowing workouts, and changes to how it calculates distance and pace for outdoor running and walking workouts. Fitness features seem to have been a pretty major part of the update.

Meanwhile, 9to5Mac is reporting, citing multiple unnamed sources, that Apple has plans to expand the Watch's health and fitness features. The report mentions a number of features that were in the original Apple Watch plan but were cut for regulatory or accuracy reasons. One feature that Apple is reportedly experimenting with, but which is unlikely to ship as a feature of a device that's not cleared by the FDA, is one that would notify the user of an irregular heart rate.

In the short term, 9to5Mac's sources say, Apple will seek to introduce blood pressure monitoring and sleep tracking. In the longer term, the company will seek to implement blood glucose tracking.

Finally, a new feature that could be hitting as soon as the WWDC is third party-generated Complications, which are tiny informational widgets on the watch face that currently can only come from Apple's own sources (battery life indicator, alarm clock status, etc.). If they are opened up to third parties, they could allow developers to display small hints about a user's health status directly on the watch face.