A recent RTE survey found that 70% of respondents bring their phone to bed with them: An extensive study in the US found that people who abstain from smartphone use in the bedroom are much happier than those who can not leave their smartphone in another room. (source: University of East London).
The study also found that those who left their smartphone in a different room experienced better sleep patterns, improvement in their relationships along with improvements to their general well being.
Even using smartphones close to your bedtime can cause poor quality and quantity of sleep (Orzechet et al 2016), especially in regards checking social media updates a few minutes before bedtime (Levinson 2017).
Perhaps you want to check your WhatsApp groups or have a quick look on Instagram before going to bed. It sounds harmless, but you are potentially sabotaging your sleep and if your phone is in the room the blue and white lights emitted can potentially cause insomnia when the lights are turned off.
Extensive research still being carried out on proving this hypothesis.
Checking your e-mail before you go to bed will usually lead to you staying up later than intended and lead to you being less productive the next morning, due to sleep deprivation.
In essence, if you want better sleep, better relationship and better general well being, research is strongly suggesting that you leave your smartphone out of the bedroom at night.