Those who can afford cars in Recife love to hate busses. They’ll tell you busses are noisy, over-crowded, infrequent, uncomfortably hot inside… you get the picture. I’ve been using busses for the past couple of years for several reasons. I don’t like driving, busses are cheaper, and the congested streets have one less car due to me.
Getting back on topic, I have observed that almost everybody has at least a low-end Smartphone. Samsung manufactured phones look to be the majority, but it is not uncommon to see phones from LG and Motorola. Apple and Nokia built phones are less commonly seen.
Phones stay mostly invisible, tucked in pant or shirt pockets, and handbags, as they are attractive targets for the opportunistic robber. Most people run a headphone from the phone to their ears, which leads me to conclude that they are actively listening to music or FM radio. I also see an increasing number of people using Facebook. The fact that they can do it for free on some carriers probably helps.
Fewer people actively talk into their phones. That the bus environment is noisy probably discourages more of that. Young, college going adults, seem to message more often than talk.
I don’t see anyone gaming that much, although an occasional person does appear playing casual games akin to Candy Crush Saga, maybe because these don’t require high-end phone specs.