Pretty straightforward. There are a ton of features, so it can be as easy or complex as you want to make it. For running I just press the right button to get the menu, tap the run icon, and then the right button is used for start/stop.
Now if you want, you can have up to three screens with customized data fields for your runs, auto-sync to your phone and then to Strava, set auto lap records, download custom faces and data fields, etc. etc.
Here's DC Rainmaker's review:
https://www.dcrainmaker.com/...in-depth-review.html (note: There have been a lot of firmware upgrades. When I first got the watch it would occasionally miss recording a turn when lap swimming, that got fixed). FWIW, battery life is ~6hrs in GPS mode (I use it for 70.3s) and a week just running as a watch.
ECMGN Therapy Silicon Valley: Depression, Neurocognitive problems, Dementias (Testing and Evaluation), Trauma and PTSD, Traumatic Brain Injury (TBI)