Citigroup now lets smartphone-equipped customers check their credit card balances, check deposits and recent transactions on a mobile device without having to log into the bank's app.

Billed as Citi Mobile Snapshot, the opt-in feature is meant to let on-the-go customers have quick access to their account data, including the last 15 transactions they made.

Citigroup announced it was piloting the feature in February.

Bank of the West, and most recently, Huntington Bank also let their customers view their balances without entering a user name and password on a device with limited real estate.