"Ban phones from bedrooms to protect sleep Among all the technology-free zones Twenge recommends, she singles out one as the most important for people of every age: "No phones in the bedroom overnight. It's just so important. Tons of studies on this. People do not sleep as well or as long if that phone is in the bedroom, even if it's off, much less lighting up with notifications." She points to the alarm clock feature as a deliberate design trap — it gives people a rationalization for keeping the phone nearby while sleeping. Buying a dedicated alarm clock eliminates that justification entirely and is what she calls an "underrated happiness-boosting gift." Source: Jean Twenge, The Happiness Lab, Social Media and Teen Mental Health"