WHO Joshua Tsuji, a third-year student majoring in computer science.

WHAT A position as a developer at Intuit, a Mountain View, Calif., software company that helps small businesses and individuals manage finances.

WHEN July to December 2012.

WHAT HE DID This year, the IRS announced it would promise tax refunds only within 21 days, rather than by a specific date. Knowing how many users of Intuit’s TurboTax software count on that refund to pay their bills, Tsuji built an app that estimates a more precise delivery date based on data provided in the tax return. While Tsuji waits for his patent to come through, Intuit will release the app to approximately 26 million people this tax season.

TODAY Tsuji is working on an app that tracks arrival times for Boston’s subway trains and hopes to add more trip-based features, like what the delay will be if you miss a train. Next up, he hopes, is getting experience at a startup.