I have yet to use it and really do not see a need for it. I would love for that button to be able to be programed to anything. I have had my watch for a couple weeks now and I do like it. It is buggy, I have already had to reset it once, The weather information stopped showing up and zero apps would work. Siri works ok on it. sometimes it does take a while for her and thats kinda annoying. I have used it with my bluetooth headphones working out and this is freedom. I really like this aspect about it. Though when I use the workout tracking it does drain battery pretty fast. I have yet to have the watch go into power reserve mode. Charging at night. I would like more watch faces, also would like to be able to add more of the information things you can click on to open up apps on the watch face. Some have more than others, Also have not used any of the digital touch stuff as I only know one person who has an apple watch and thats my boss, we are good friends though, so i suppose I could send him my heart beat. lol no I don't think so.