Nagi

Nagi records the whole night with just the phone's own microphone: snoring, coughing, how loud and how long, when it peaked. If you already track sleep some other way, its score and stages show alongside, with trends and a full history over time. Everything is processed on the device, nothing is uploaded. Building it from Japan first, where snoring and hay fever season drive a big share of the searches most sleep apps in English miss. Free to record.