Some people also use their iPhone as an alarm clock. Moreover, mobile phones make it easy to check emails before going to sleep. You can also do office work while staying in touch with friends on social networks.
It is true that your smartphone can help you wake up in the morning, but at the same time it can prevent you from falling asleep at night. Studies conducted in 2008 found that mobile radiation makes it harder for users to fall asleep and sleep soundly.
You should not keep your phone under your pillow before going to sleep, or you may be tempted to check it over and over. As a result, you will take longer to fall asleep. Even if you do not check it, the sound of an incoming message will disturb your sleep. Most mobile phone users want to be reachable 24/7. According to a study conducted in Sweden, excessive mobile phone use can cause sleep problems, depression and stress. You may want to return a call or text message almost instantly, which makes you more addicted to your phone. Some users even reply to text messages while half asleep.
To avoid these problems, you should keep your cell phone out of reach before going to sleep.