"I think the more interesting conversation to have is really around the quality of that screen time," he said, adding that parents needed to set an example by reducing their own phone usage so that children were not just "looking at the black back of the phone".
Spiegel is married to the Australian model Miranda Kerr, and Flynn is her son from a previous marriage.
Numerous other tech leaders have spoken about limiting or moderating the time their children spend with the products they create, including Steve Jobs, Bill Gates, Google's chief executive Sundar Pichai and Apple's chief executive Tim Cook.
Mark Zuckerberg's sister Randi has said there are "no devices" allowed in the room during dinner time, and allows her young son to earn extra minutes of screen time through good behaviour.
An increasing number of Silicon Valley parents are stipulating that their nannies do not use mobile phones in front of their children to avoid encouraging them, while the Waldorf School, attended by many children of Apple and Google, believes that children should not be exposed to technology before the age of 12.
Spiegel also offered cautious praise for the "philosophical approach" to regulation shown by the EU – a hint that he may back efforts to pass a privacy law for the US that draws on Europe's GDPR.
Snapchat denies that it designs its products to be addictive, saying that it wants to encourage people to develop positive and meaningful relationships with each other online.