BigTime Mobile
Rebuilding an App From Scratch
From Broken to Beloved: A Mobile Comeback Story
UX & Research Director | Made at BigTime, 2023-25

The Team:
UX Designers: Monika Gontarz, Bartosz Ujma
Vendor Support: DEPT Agency
PMs: Agata Szocik, Mart Pat Holtrop, Leia Pitcher
Devs: Patryk Kizak, Wojciech Serewis, Nick Devereaux, Jon Cain
BigTime Mobile was in urgent need of modernization. As the primary tool for entering time and expenses on the go, the app had fallen behind in both performance and usability. I was the UX Director for the full redesign and rebuild, from early concepting with a vendor partner (DEPT) to an internal team handoff. The initiative centered on re-establishing user trust, improving reliability, and creating a more intuitive mobile experience. Legacy app ratings were at 2.7 stars (the lowest among competitors), and customer trust was slipping.
The Challenge
The legacy app suffered from performance issues, confusing workflows, and missing features that impacted users in critical day-to-day tasks.
Key Focus Areas:
Resolving Outdated UI and ambiguous workflows
Reducing Frequent bugs and broken receipt uploads
Improved feature parity with the web platform
Improve low app store ratings (2.7 Stars)
Migrate users to the new experience

BigTime Legacy App
The Approach
Working with an external vendor, we worked as fully embedded teams for discovery and development. Here are some processes and areas that we discovered along the way:
Discovery: Listening, Not Guessing
We began by grounding the redesign in customer feedback and support data. I worked with the Program Managers to develop a series of discovery sessions (over 30), surveys, and usability sessions to pinpoint specific frustrations with mobile time entry, timers, and expense submission.
Stabilize, Then Rebuild
We quickly patched the legacy apps to fix urgent issues, address App Store violations, and rebuild user trust. Then, we kicked off a parallel effort to rebuild the apps from the ground up. The process started with an intense two-week sprint to diagnose every structural weakness.
UX Improvements with Measured Impact
The new patterns remained familiar, but we introduced meaningful enhancements to ease pain points. These included simplified timer controls, offline access, improved receipt handling, and homepage action items designed to streamline daily use.
Vendor Engagement & Agile Iteration
We worked closely with DEPT during the first 60% of the project. We moved quickly from early prototypes to working builds, focusing on component-level improvements that could be validated with users.
Transition to Internal Team Ownership
About halfway through, we began transitioning the work to our newly built internal team. I remained involved through multiple iterations and sprints to introduce it formally to the Google and Apple App stores.
Marketing and GTM Collaboration
We partnered with the marketing team to craft clear messaging, create video assets, visual assets, storytelling, and overview videos that resonated with both existing customers and prospective users.
The Result
We sucessfully rebuilt each screen with simplified UX patterns. In this process we also developed a new mobile-first design system.
2.7 ★ → 4.4 ★ Rating


Key Mobile Refinements
Updated UI with improved component consistency & patterns
Credit card expense tagging, time duration increments
Time & Expense resubmission flows
One-tap timers and offline access
A redesigned home screen focused on quick actions
A full native rebuild for iOS and Android

Ongoing Improvements

After launch, we closely tracked adoption metrics and gathered user feedback, which revealed opportunities to enhance the home screen, time entry, and expense experiences. Customers needed faster access to key actions and clearer visibility into their schedules.
I led some focused research sprints with UX Designers to validate new concepts for a more actionable, glanceable home screen. We prioritized quick access to timers and task summaries, and tested calendar-based time entry views to improve control and planning. With these updates, we also updated the navigation for quicker access to Settings. These updates are part of our ongoing, research-driven roadmap to streamline workflows and better support BigTime's customer base.
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