The two I know of that are still running are Dreem (the one I went with) and Philips SmartSleep. I chose Dreem at the time because it looked more comfortable (

The two I know of that are still running are Dreem (the one I went with) and Philips SmartSleep. I chose Dreem at the time because it looked more comfortable (no ear covering) and was more readily available in my part of the world. It looks like Philips also has consumable components, which I'm not a fan of. I've been using it for months now and I'm happy with it. It also has a feature to "stimulate" your brain to improve deep sleep and it tells me it's quite effective (comparing with stimulation sleep to without stimulation sleep), though I can't say I've noticed a huge difference.