8 minutes

First published: December 14, 2016

Managers can approve spending limits and make other administrative decisions anytime, anywhere. And employees can gain access to expense-related information through their smart phones and mobile devices.

A typical use case: An HVAC service company uses PEXs to authorize the funds its field technicians need to purchase gas for their trucks and parts to repair customers’ equipment.

The Need

One of Softjourn’s first projects with PEX was to design and develop mobile apps that make it possible for card service administrators and cardholders to track expenses on the go. A primary goal was to create a user-friendly interface for phones and tablets. 

The Softjourn team proposed a cost-effective solution: Build a hybrid PhoneGap application in HTML5 that runs on iOS and Android devices.

This solution worked well for several years, but advances in technology made it apparent that a new release of the apps would be desirable. PEX turned to Softjourn for assistance in addressing several issues. The company wanted to create user interfaces that were native to various mobile devices, whether iOS or Android. PEX also wanted to take advantage of a development platform that included pre-built UI and standard controls, transitions and animations. Finally, PEX wanted to improve the speed of performance, which could be slowed by code running in web view.

The Solution

A .NET shop, PEX chose Xamarin, a common language infrastructure (CLI) and common language specifications development environment, because of its ability to address these concerns and also because of potential ease of future functionality build-outs. 

Using Xamarin.iOS and Xamarin.Android, Softjourn developers created user interfaces that look, feel and perform like a native application. In addition, the Softjourn team added a receipt-capture option. Previously, PEX users recorded their expenses manually. With receipt capture, they continue this process but can now use their phone cameras to photograph receipts and upload them to the app to provide visual proof of an expense.

Softjourn developers also made another important change. Originally, administrators and cardholders each used a different application. Now they use a single app, with login credentials based on user type.


  • C#6
  • .NET 4.6
  • Xamarin.iOS
  • Xamarin.Android

The Benefits

Today, PEX users, whether they are employees or managers, enjoy rapid performance from updated applications that look and feel native. And PEX benefits from a development environment that allows sharing of code across all platforms and a development partner team that can leverage it to create great user experiences.

PEX - softjourn's prepaid client

PEX, a New York fintech company founded in 2006 is a platform provider of next generation corporate card and expense management solutions for businesses. The PEX service enables companies to empower their workforce with flexible options for employee spending, as an alternative to credit cards or cash expenditures.