With the growing use of mobile phones, it's not hard to imagine a day when people will employ them for everything, including all their money tasks and even additional financial activities.

By 2015, the mobile worker population -- people who work using their smartphone devices -- will reach 1.3 billion, IDC has predicted. People probably won’t just be working on their phones. They’ll also be completing their daily errands (like managing their money) on the go. 

Some personal-finance apps on mobile platforms are Level MoneyMintSimple, Moven, GoBank, Check, BillGuard, Wise.ly, Numbrs (in Germany) and Tink (in Sweden). My own company, Moneytree, offers a product in Japan. At a time when mobile devices are becoming so closely linked to the way individuals engage with the world, eventually people’s relationship with money may become intricately tied to their phones. 

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Mobile use this year is projected to surpass desktop Internet use, so developers are responding to the market with elegant choices. In order to reach Gen Y and early-adopter customers, banks and financial institutions need to be strategically positioned with a mobile-first mentality because that’s how these people lead their lives.

The mobile trend is spreading across different demographics and the setting doesn’t matter. According to 2013 research by Ofcom in the United Kingdom, researchers found that 81 percent of smartphone users have their devices switched on all the time, even while they sleep. Fifty-one percent of adults used their phones when socializing with others and 23 percent during mealtimes. And 22 percent of adults even admitted to using their phones in the bathroom.

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Employing apps for money tasks. The rising use of mobile devices will create a tectonic shift in banking and already some mobile apps like Square and Venmo, are changing the way people deal with money.

For banks and financial institutions scrambling to capture mind and market share, having a mobile-first mentality is critical. Apps can do more than extend existing channels. They can also leverage technologies unique to mobile. This change is so fundamental, that perhaps one day there won't be “mobile banking” anymore. It will just be called “banking.”

Sixty-one percent of Americans believe smartphones will eventually replace cards and cash, according to a 2012 Harris Poll of 2,383 adults. As more companies let users make payments by scanning their phones, carrying cash and credit cards will become less necessary for consumers. Starbucks has 5 million mobile transactions weekly on average and reported in January that 30 percent of its total payments came through the Starbucks card or app.

Square and Uber have proved that customers will use smartphone apps in place of physical cards, suggesting a possible future with "transactionless" transactions. And the feeling that a person has upon exiting an Uber car, without handing anything over, is amazing. 

Money has always been about transactions, a shift from one person to the another, and companies like Square and Uber have developed technology to match those economics. Players in the personal-finance market, however, are learning that mobile devices can do more than merely serve as transaction tools. In the future designers of personal-finance management apps may even offer users real-time insights and intelligence to improve their lives with information on their financial status and habits.

Some banks, however, have been delinquent in developing compelling mobile apps for customers or do not have mobile-enabled websites. 

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Designing for mobile devices from the get-go. A minimalist design philosophy has pervaded lifestyle products and media, and now, more than ever, mobile technology. A well-designed mobile app -- including one for personal finance -- does the right thing not everything. Unlike when people access online budgeting software or a website, when users tap a mobile device they don’t want to be overwhelmed by data, information and processes. While on their phones, users only want to get what they need. 

An app should follow the needs of the user, not the other way around. And what better device is there for learning about a consumer's needs than an object with an always-on interface that follows him or her around?

By starting with a mobile app in creating a product (as my firm and Instagram did), companies can optimize functionality and the user experience to deliver the exact information and functionality that consumers need in the palm of their hands.

A mobile-first mentality means being attuned to “progressive enhancement,” a powerful methodology that lets app developers concentrate on building the elements essential for a user. Designers start by loading the absolute bare essentials on smaller platforms. This leads to a snappier experience that avoids unnecessary lags. Then additional resources are loaded strictly on an as-needed basis to platforms that can handle them well.

Streamlining and optimization of data are what defines the beauty of a truly mobile experience. A minimalist approach to data aggregation and display and the aesthetics of the user interaction all can contribute to a consumer experience focused on the essentials that seamlessly integrates with people's lives, not burdening them with protocols and unnecessary processes. 

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