The mobile device is becoming the first screen people turn to.

The mobile device is fast becoming the first screen, as a recent study shows. According to Millward Brown’s survey of more than 12,000 people aged 16 to 44 across 30 countries, these mobile users spend a total of 417 minutes a day looking at screens: Smartphones claim 35 percent of this time, while TV gets 27 percent, laptops/PCs get 26 percent, and tablets take up 12 percent.

Of the total screen time, simultaneous use with TV is taking place around a third of the time. Millward Brown then breaks down simultaneous time into two categories: “stacking,” or using a digital screen for matters unrelated to the television, and “meshing,” which means using the second screen to enhance the TV experience. Those who stack tend to be filling time during ad breaks or watching TV somewhat halfheartedly. Those who mesh are mostly looking for more information or engaging in social media chatter about a show. Millward Brown says Americans are most likely to stack, while viewers in Thailand, the Philippines and South Korea are most likely to mesh.

Increasingly, brands will have to develop a compelling presence across screens, with an emphasis on mobile—a difficult shift, considering that consumers are far more favorable to ads on their TV than on their mobile device and more apt to pay attention to TV ads. Millward Brown found that 41 percent of respondents are very/somewhat favorable to TV ads, and 72 percent say they pay at least some attention, while just under a quarter are favorable toward mobile ads, and only around half say they pay some attention.