Whether or not you have a smartphone is closely related to both how old you are and how much money you make, according to a Nielsen survey in January of more than 20,000 mobile consumers.

While overall smartphone penetration stood at 48 percent in January, those in the 25-34 age group showed the greatest proportion of smartphone ownership, with 66 percent saying they had a smartphone. In the same age group, 8 of 10 of those that had gotten a new device in the last three months chose a smartphone. Among those who chose a device in the last three months, more than half of those under 65 had chosen a smartphone.

But age isn’t the only determinant of smartphone ownership. Income also plays a significant role. When age and income are both taken into account, older subscribers with higher incomes are more likely to have a smartphone. For example, those 55-64 making over 100K a year are almost as likely to have a smartphone as those in the 35-44 age bracket making 35-75K per year.

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