South African bank FNB says that 18- to 25-year-olds have shown the highest growth in uptake and usage of its mobile banking app among all age groups, IT News Africa reports.

In 2011, when FNB launched its mobile app, 18- to 25-year-olds accounted for 6 percent of the bank's app users. That age cohort "now account for 14 percent of active users on the platform, which correlates with the growth in checking accounts for this age group," Giuseppe Virgillito, head of channel, banking app, FNB Mobile and Connect, said in a statement.

As at December 31, 2013, FNB's banking app had seen a growth rate of more than 100 percent, the bank said. The FNB banking app reached the 750,000 active user mark early in 2014 and is still showing a month-on-month increase in number of transactions and active users.

Although the number of checking account users aged 18-25 is small in comparison to other FNB customer groups, the number of 18- to 25-year-olds with FNB checking accounts has doubled since 2011. Their usage of FNB's app revolves around day-to-day transactions such as balances, payments, transfers, purchasing prepaid airtime, data and SMS purchases.

"We think that the growth in the 18-25 year-old market is down to the characteristics and trends shown by the two different generations that overlap within this age group," Virgillito said. "Generation Z, also known as digital natives, were practically born with smartphones in their hands and will naturally adopt digital banking trends once they open their own bank account. On the upper end of the age group are the Generation Y group or Millennials, who are young, working and have adopted digital channels with ease and for on-the-go banking."

FNB said that 80 percent of all transactions on the FNB banking app take place between 7 a.m. and 7 p.m. daily. Unlike FNB's Cellphone Banking service, which is mostly used for prepaid transactions such as prepaid airtime and electricity purchases, the most popular transaction type on the FNB app are payments, which make up 50 percent of transactions made via the app.

"As the increase in banking app users from generation Z and beyond give birth to a new type of banking customer, we are expecting to see new banking needs and trends emerging, and customers who overall interact with their bank on digital channels," Virgillito said.