I've used Beddit, quite good but company has been bought by Apple and I don't think it will ever get any updates as a standalone product. The most advanced and

I've used Beddit, quite good but company has been bought by Apple and I don't think it will ever get any updates as a standalone product. The most advanced and exciting one is probably the Dreem headband, an EEG that also has features to fight insomnia and even attempts to improve your deep sleep : https://dreem.com/en/ https://dreem.com/en/ Quite pleased with it, even though the app still has teething problems.