The two largest carriers in the U.S., Verizon (VZ) and AT&T (T), have been heavily promoting their shared data plans since they launched this past summer. Now that the days of unlimited data are coming to an end, users are more cautious about what they download. New research from NPD Group revealed that Android smartphone users have begun to prioritize Wi-Fi over cellular networks, Fierce Wireless reports. The research firm found that users downloaded an average of 2.5GB per month on Wi-Fi, compared to roughly 870MB of data on cellular networks. A further breakdown of the numbers revealed that young adults aged 18 to 24 unsurprisingly use the largest amount of cellular data, averaging 1.05GB per month, compared to adults aged 55 and older who average just 750MB a month. On Wi-Fi, users between the ages of 25 and 34 used the most data, however, averaging 3.01GB per month, compared to 1.42GB of Wi-Fi data used by adults aged 55 and older. NPD’s findings come from a sample of 1,000 Android smartphone owners on various networks.