Amazon Chime has this feature. And when I worked at Amazon, it was very useful in helping me to be on time for my meetings. I've been working at RingCentral now for three weeks, and I've already been late to a meeting because I lost track of time while working.The way it works in Amazon Chime is that Amazon Chime rings me for my meeting with the option to accept, decline, or indicate that I'm running late by selecting a number of minutes from a dropdown (e.g., 2, 5, 10, 15). If I indicated I was running late, it would then ring me again a minute before that time was up. It would also let the other meeting participants know I was running late by however many minutes I specified. Of course, I could also join at any time and didn't have to wait for the call from Amazon Chime.