How We Built a To-Do List App to Comfort Control Freaks


Dusfer is a notebook, a to-do list, a calendar, media storage, and a collaborative work platform all rolled into one. It manages a wide range of personal and business tasks: from sharing a grocery shopping list with family members to running startup projects.

Tech stack

Backend:Nest.js, TypeScript
Integrations:iCloud, Apple ID, iPhone Calendar
Storage:AWS, SDN

Our role

UX/UI Design, Mobile Development, Backend, QA, Support

The challenge

The founder decided to professionally enter the mobile applications market with his newborn company called Thunder Apps. We were honored to work on the first two projects: first the language learning app Akler followed by Dusfer.

This time, he fancied an app that would seamlessly integrate the entire user agenda in one place. It had to be well-suited for solving radically different types of tasks and be simple to use on the smartphone — as if Todoist and Telegram had a baby.

Third-party teams have already attempted to get moving on the work before it was passed to Rocketech. We inherited the project with a partially developed frontend that turned out to be non-functional.

The discovery sprint showed that there was no point in trying to keep working with the old code. Instead, we summoned a big team to re-invent the app from scratch: improve the logic, polish the design, and develop an MVP.

Third-party teams designs

The solution

We created a functional design that syncs all user's notes and tasks without cluttering the interface.
All tasks are organized in a convenient feed. In order not to get lost in different types of objectives, they are sorted into folders: Habits, ToDo, Notes, Ideas, Goals, Done, etc. Users can also view the tasks in the calendar mode.
Complex social mechanics: users can invite other people to the project, collaborate, assign tasks, leave notes and comment on them, change the access settings, and many more.
The data is safely stored in the encrypted database on the server. Accounts are protected by PIN code/FaceID/TouchID and two-factor authentication. On top of that, users can lock selected folders with passwords, blacklist people, and filter the invites.
The app syncs with iCloud, iPhone calendar, and thousands of servers that we configured via API. The future sprints will include a number of integrations with popular workflow trackers: Jira, Trello, Asana, etc.
Complex architecture allows working in offline mode (syncs with the backend).
Multiple sharing and export options.
A unique custom-made mobile editing tool. Users can attach images and videos to each task and note, add charts, voice memos, tags, and sketch out ideas with a drawing tool.
Automation testing was run to compare expected and actual results and debug the app.
Full business tasks functionality: deadlines, subtasks, timelines, comments, locations, alerts, reminders, and easy search by tags.

Have a digital product idea but don't know where to start?

From the initial market research to launch — we'll happily guide you throughout your business journey.


The end result is a minimalistic iOS app based on the best market practices.
A big full-cycle team implemented an extremely complex MVP in a span of 9 months with 10 people in the team.
We designed over 220 screens.
Built an enormous architecture and functionality.
We followed the Test-Driven Development (TDD) to create the MVP. That allowed us to make sure the code is working every step of the way.
The devs balanced a complex internal architecture with a functional UI. We fit the entire functionality into slightly over 200 screens — thus, Dusfer stays simple even with infinite threads and a gazillion of details.
We reduced the chance of data leaks to zero thanks to complex encryption and privacy settings.
Next in line: integrations with Trello, Jira, Asana, and other popular project management tools.

Talk to us!

Send us a message and we'll get in touch with you as soon as we can.
United States+1