How to solve big problems and test new ideas in just five days.

Headspring Expense Tracker

Problem Statement

Headspring had a policy of rotating us to the bench for 2 weeks after a client engagement.

This allowed us to do some ‘house cleaning’ and light prep work before our next client engagement as well as knock out some personal development.

Deran, the Houston Office lead, and I had just finished “Sprint” and decided to tackle an internal project.

Long Term Goal

Create a simple app for Headspringers to easily submit expenses for reimbursement.

Solving big problems

Sprint Questions

  1. Can we access the current system (xero) API and write to it?
  2. What are the current major pain points?
Sprint book

Mapping the users flow

Expense Tracker User Flow


During our interview with the head of Headsprings accounting we identified a couple key issues to tackle.


  • Currently expenses are submitted ad-hoc to an email address expenses@ that she then receives


  • There are no defined standards so an email will arrive with PDF, Jpeg, GIF, PNG or any other acceptable email attachment format


Expense Tracker wireframes

Whiteboard breakdowns

During Tuesday’s ‘sketch’ session Deran and I took turns doing various walk-throughs on portable whiteboards.

The sessions broke down like this.

30 min – solo whiteboard flow

60 min – ‘share’ and discuss

Rinse and repeat

1 final session where I created wireframes in Balsamiq based on our previous conversations.

Expense Tracker wireframe annotated

Paper Prototype

Using the POP app by marvel I wired together a prototype to conduct some paper prototyping tests on fellow Headspringers.

Heartland initial wireframe

User Testing

Using the POP app by marvel I wired together a prototype to conduct some paper prototyping tests on fellow Headspringers.

We conducted 8 in-office interview/ test sessions and 9 remote sessions with members in our Austin office.

  • 2 – Austin and Houston Office Managers
  • 4 – Sales team members
  • 2 – Accounting team members
  • 9 – Austin and Houston based developers
Expense Tracker testing
Headspring – Sprint – Knapp, Zeratsky & Kowitz

Final Thoughts

Are 5 days enough to “solve big problems and test new ideas” as the book contends?

I’m still on the fence. Technically we did… sort of. 🙂

Tesler’s Law: We did identify that our simple little app, while it did address the accounting managers’ issues, just shifted the burden of effort onto the users needlessly.

(They need to be able to submit more than 1 expense and that was NOT doable in our timeframe)

Headspring Expense Tracker
Headspring – Sprint – Knapp, Zeratsky & Kowitz


Heartland User journey

The following week Deran and I finished the app with the feedback we had received during testing.

Sometime shortly afterward, Kiet, one of our Houston developers knocked out the multiple receipt problem.