What if a rough sketch, a good idea, and an AI collaborator were enough to build a real app?
That is exactly what I set out to discover—and the result is TimeTrack Invoice, a new time-tracking and invoicing app now available on Apple’s App Store.
I’ve been experimenting with cloud AI for some time. I started with Cursor, a version of Microsoft’s Visual Studio Code that can work with several large language models, including ChatGPT, Claude, Grok, and Gemini. Eventually, I settled on Claude Cowork. It keeps track of my sessions, lets me separate projects, and—most importantly—helps me turn an idea into something that actually works.
The problem that sparked the app
Friends often ask me to work on projects for them. I enjoy the work, but I have never been a great record keeper. Tracking which project I worked on, when I started, when I stopped, and what should appear on an invoice can become a project of its own.
So I asked a simple question: Could I use AI to build the straightforward time tracker I wanted to use myself?
I did not want to limit the idea to Apple devices. I chose Flutter and its Dart programming language so the same codebase could support macOS, iPhone, and Android. I had never written a Flutter app before—but I was not going to let that stop me.
From paper sketch to working software
I drew the interface I had in mind on paper, took a photograph, and sent it to Claude. Within minutes, I had a working user interface that looked remarkably close to my sketch. That moment felt like a glimpse of a new kind of programming: describe the destination clearly, then work with the AI to build the road.
I developed the Apple and Android versions in parallel. Although I worked on the project in spare bursts, I estimate that the complete build would have taken about one focused week. Claude also guided me through the unfamiliar process of preparing and submitting my first app to Apple’s App Store.
TimeTrack Invoice is now live
Download TimeTrack Invoice from the Apple App Store. The direct link is the easiest way to find it; a regular search may place it well down the list among many other time-tracking apps.
I deliberately kept the experience simple:
- Select the project you are working on.
- Press the large Start button when work begins.
- Stop and restart the timer whenever a phone call, break, or interruption pulls you away.
- Generate a professional invoice at the end of the month and email it directly to your client from your phone.
The app stores your entries locally, keeps each project organized, and costs $4.99—one of Apple’s lowest paid-app tiers.
Want to help shape what comes next?
I have a limited number of openings for serious beta testers. I’m especially interested in hearing from people who bill by the hour: repair technicians, consultants, tradespeople, freelancers, and other independent professionals who need accurate records without unnecessary complexity.
Approved testers will receive a free copy for the 90-day beta period. In return, I’m asking you to use the app regularly and tell me honestly what works, what does not, and what would make it more useful.
Building TimeTrack Invoice reminded me why I still love technology: a useful idea can begin with nothing more than a problem, a pencil sketch, and the willingness to try something new.
Enjoy—and let me know what you think.