Relevant to people who build webapps/server side apps today: http://www.netbanker.com/2013/03/metrics_mobile_traffic_at_the_10_largest_banks.html
About 2/3rd of users who have access to mobile banking use only their mobile access.
Some of our biggest users are probably best known as "mobile apps" - so if you aren't familiar with mobile development - it pays to at least keep an eye on it, as you probably will be involved with mobile projects at some point.
This is timely - as just last week the ios-clickstart was made available! (not a bad place to start).