Bo is a prepaid card which allows customers to track spending closely and is complemented by a bright yellow debit card aimed at younger audiences.
Unlike a traditional bank account, Bo doesn't yet have the facility to accept salary deposits or pay bills, so it cannot be used as a main account.
It's envisioned as a rival to digital challengers like Monzo and Starling Bank, albeit with a limited set of features at launch.
Bo is being touted as a way for customers to get on top of their spending by using a second account with intelligent tracking, budgeting and goal setting.
These are features similar to those offered by Monzo when it first launched, although they soon moved to become a full-service bank with salary pay-in, direct debits and even digital ISAs.
NatWest will be hoping to capture some of the younger market who want more from their banking apps than merely showing them their transactions.
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They'll also receive a contactless yellow debit card and have access to their cash while overseas using the Visa exchange rate.
Bo isn't pretending to be anything it's not - it clearly tells potential customers to leave their bills and direct debits where they are and focus on tracking and budgeting with their new Bo account.
However, this means it's essentially a prepaid card with excellent app features, and that isn't exactly unique among providers these days.
Challengers like Monzo and Starling might have gone down the full-service route and be attracting hundreds of thousands of customers, but there are several other major players on the market.
For instance, Monese is targeted towards immigrants and travellers who may not have a fixed address, while Revolut is also targeted towards travellers.
It's worth pointing out neither of these are FSCS protected as Bo, although a drawback with Bo is that it can only be used by UK residents.
There have also been some notable failures in the prepaid card sector, however, with youth-orientated Loot going into administration in May when it couldn't secure more funding.
All this indicates that Bo may have a battle to prove itself relevant in a busy digital marketplace.
One of the major things Bo has going for it, though, is the connection with NatWest who share their banking licence with the new challenger.
Potential customers who may be unwilling to try a banking app from a newer bank like Monzo might trust the NatWest-backed Bo to keep their money safe.
However, this could prove to be a contradiction for Bo, with them hoping to pick up the younger demographic by engendering trust when the younger generation are more likely to try new brands anyway.
It's certain the mobile banking revolution is in full swing, and app usage is set to overtake branch visits by 2021 according to research by data consultants CACI.
Bo is a feature-laden addition to this digital focus and has the potential to be an excellent tool in its own right - if it can find an audience.
Learn more about mobile only banks and what to look out for when signing up in our dedicated guide.
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