Baby John Tan loves spending time with his friends Dave and Ava, but his parents are concerned about his choice of company.
Although Dave and Ava help the 16-month-old learn English through nursery rhymes, they live behind an electronic tablet screen.
John is allowed to watch them on YouTube at his grandparents' house when his parents are at work.
But John's parents, Mr Tan Wei Yi, 32, and his wife Stacy, 33, keep him away from a screen at home.
The dilemma they face is increasingly common in Singapore. The use of screens, from mobile devices to computers and television, is ubiquitous, fuelled by the availability of smartphones and tablets.
A 2015 study published in the Early Childhood Education Journal showed that children under the age of seven in Singapore spend at least an hour a day on smartphones and touchscreen tablets.
This figure may be under- reported, said Dr Jiow Hee Jhee, 45, associate professor of health and social science at the Singapore Institute of Technology. He added that the prevalence of screen time may be much higher.
The minimum amount of time a day that children under seven in Singapore spend on smartphones and touchscreen tablets, according to a 2015 study published in the Early Childhood Education Journal. An expert said this figure may be under-reported.
The constant availability and portability of handheld devices make their influence more complex than older technology.
"In the past, children were able to tell how much time they spent on devices like gaming consoles and TV. But now, the problem is more pervasive with smartphones and tablets," said Dr Jiow, who is a member of the Media Literacy Council.
He added: "There are children and even parents who cannot tell me how much time they spend on the devices because they are using them all the time."
Caregivers also use mobile devices as babysitting tools when they do housework or when they simply need to take a break from taking care of the child.
Baby John's father, Mr Tan, said: "I don't let him watch YouTube when he's with me. But it's harder for my parents to keep him occupied and entertained."
However, excessive screen time can create problems with posture and repetitive stress conditions such as carpal tunnel syndrome.
Children who have too much screen time may refuse to go out- doors to get much-needed exercise.
Of greater concern are the unseen risks that the overuse of mobile devices may have on their mental health and development.
Research in South Korea on children aged 24 to 30 months showed that the delay in language-learning increased proportionately with time spent in front of the TV.
Toddlers with two to three hours of daily viewing had a 2.7-fold higher risk of delay in language- learning than those with less than one hour. And toddlers who spent more than three hours per day on devices had a three-fold increase in the delay of language-learning.
Children learn about social relationships through watching others around them. Studies in very young children suggest that screen usage is a risk factor for reduced psychological well-being.
An analysis of infants in Thailand showed the increase in TV exposure from six to 18 months of age was associated with emotional reactivity, aggression and externalisation behaviours.
Experts are concerned that the rise of mobile technology will only exacerbate these issues.
Dr Daniel Fung, 50, chairman of the medical board at the Institute of Mental Health, said: "Too much screen time takes young children away from real human interaction. This can lead to impaired social learning and damage their emotional development."
Another problem is addiction, as mobile games and programmes are designed to be immersive and stimulating.
Dr Jiow said: "Addiction cannot be measured in hours, it's more about the type of usage. As long as it causes damage to a child's social or academic functioning, it can be considered addiction."
ARE SCREENS REALLY THAT BAD?
Although screen time has its dangers, the use of technology in appropriate amounts may be useful and even beneficial to children.
High-quality programmes and games for young children are commonly used in pre-schools.
Ms Thian Ai Ling, 43, deputy general manager of My First Skool, said: "For us, technology complements teaching. It is designed to be age-appropriate and does not involve passive viewing.
"We let children aged from four to six use technology-enabled toys and get them to try out simple coding."
In the end, it may be more about content and the level of engagement with devices, rather than the amount of time that children spend using them.
Dr Fung pointed out that children under two should be exposed to as little screen time as possible. This is based on a guideline from the American Academy of Paediatrics.
Experts emphasised that parents should take charge of their children's screen time, especially for the very young ones (see other story).
Dr Fung said: "Children need guidance and human interaction. Parents should be more involved in their early years, which are the most important for development."
Do’s and don’ts for tiny tots
Children may face negative effects from too much screen time. This includes television, laptops, tablets, game consoles and smartphones. Here are some guidelines for parents:
1. Children below 18 months should avoid screen time, except for video-chatting with family members.
2. Children from 18 to 24 months of age should be able to access high-quality programming if their parents choose to introduce digital media to them. Parents should watch it with them to help them understand what they are seeing.
3. Children between two and five years old should have no more than an hour a day of screen time with high-quality programming.
1. Vet videos, games or apps for violence and aggression before letting children use them.
2. View media together with them to help them understand what they are seeing and apply it to the world around them.
1. Don't introduce screens to children too early.
2. Don't allow screen time during meals, playtime and bedtime, if possible.
•Source: Dr Daniel Fung, chairman of the medical board at the Institute of Mental Health; American Academy of Paediatrics