Three years ago, Aishah Iqbal had just qualified as a doctor and was finding it a "steep learning curve". She often felt overwhelmed at work – and whenever she took out her phone and saw "all these messages coming up", she felt worse. "It was very easy to get distracted from why I'd pulled my phone out, or to feel like there were so many people that I needed to reply to immediately."

When we talk about the fragmenting effect of technology on our attention, or the dopamine hits that keep us refreshing our feeds as if they are buttons on fruit machines, we are often thinking about notifications: the pings, pop-ups and glowing red dots that pull us back into our phones, and push us from app to app.

According to one small study conducted in 2014, mobile phone users receive an average of 63.5 alerts every day, with most viewed within minutes – whether the phone is on silent or not.