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Project background

Quittercheck is a tool for those who want to quit smoking. Users commit to stopping smoking for a desired amount of time and declare an amount of money they will be charged if they fail.

What is unique about the Quittercheck app is that it uses modern media such as video - recorded by the user - to fight the addiction rather than encouraging the use of smoking cessation aids.

This application supports the user's willpower through a commitment to specific behavior and a system of penalties and rewards.

During the cessation period, users are randomly asked to perform a nicotine test in front of the camera. They are also given a set of instructions before taking a video test.

Then they record themselves performing a nicotine test and show the results. Quittercheck employees verify test results. If the test is passed, the user is paid a reward.

Quittercheck is a healthcare app. It focuses on helping users quit smoking. And successfully get rid of the bad habit. It targets smokers in the U.S. The application provides video processing. Along with end-to-end order management.

Healthcare Industry

Healthcare Industry is vast when it comes to the use of technology. From applications supporting a healthy lifestyle and nutrition, supporting physical activity, and emotional and mental stability, to those improving the work of doctors and hospitals.

A few years ago, it would have been unthinkable that a mobile application could also support you in quitting the addiction. However, over time, users got used to seeking help via the Internet and the tools they use every day - their cell-phone.

In 2019, nearly 14% of the U.S. adults aged 18 years or older smoked cigarettes. It means an estimated 34.1 million adults in the United States currently smoke cigarettes. As a result, more than 16 million Americans live with a smoking-related disease.

In 2015, 68.0% of adult smokers (22.7 million) said they wanted to quit smoking. Therefore, there is potentially a massive market for smoking quitting tools.

With those recent changes in human behavior, new opportunities arise. One of the companies that use these opportunities is Quittercheck - a healthcare app that focuses on quitting smoking.



Collecting videos

Order management



Users record themselves performing a nicotine test. The video ends when nicotine tests display a positive or negative result. Such videos may take up to 20 minutes. Once uploaded to cloud storage, it may be displayed by an administrator who confirms the test’s execution and result.

Scope of work

We were asked to prepare an app that supports and automates the process of collecting videos performed while doing a nicotine test.

It was supposed to be available on both iOS and Android, so naturally, we picked Flutter for mobile and .NET for the backend. We also created an admin app that lets administrators review users' videos and manage their payments.

Our client wanted us to limit the number of tools included in our tech stack; therefore, we picked Flutter for Web for the web development of the admin app.

We also knew that our client would like to onboard his own small team of engineers at some point in time. Having all frontend (both mobile and web) done in Flutter allows the client to limit competencies they will have to look for a permanent contract.

We've investigated and consulted business and legal compliance. As a result, we've provided the app with integration with 3rd party system responsible for proper sales tax calculation.

We selected TaxJar (a fully integrated solution with the Stripe toolkit) due to its fast implementation, reasonable pricing (better pricing options than Avalara or Quaderno, which were also considered), and sound requirements coverage.

As a result, we were able to calculate tax rates based on the user's address and the type of chosen products. Also, due to frequent money transactions between users and the platform, we've proposed and implemented a payment flow that limits transaction fees to a bare minimum.

Here you can read how we limited a video upload to a specific time frame based on this case.

Review of our work

Quittercheck logo

Internal feedback on LeanCode's solution has been strong regarding its speed. An external auditor praised the app's architecture. Their team showed commitment to delivering for the client and provided attentive service even after delivery. They work well with startups. 

Trevor McGerr
Trevor McGerrFounderQuittercheck
Meet our expert

Let's talk!

Our team has delivered over 60 mobile apps with 5-star client reviews only. Send us a message, and we will find the solution and service that suits you best.
Łukasz Kosman, Co-founder and CEO at LeanCode
Łukasz KosmanCEO at LeanCode

Key takeaways

  • Long video recording and uploads may cause many issues, depending on the user's device, operating system, and human error.
  • We've designed and implemented a video recording and upload process that considers connection issues, accidental recording interruption, sending past deadlines, lack of device memory, and several other factors.
  • We've also fine-tuned the upload process to work with many different devices operating on other OS.
  • We've run an extensive analysis of payment providers. We were looking for a platform that lets us collect one-time payments, recurring payments, deposits, and refunds.
  • Due to frequent money exchange between a user and the platform, we've developed a set of features that limit transaction fees.

Additional value delivered

LeanCode helped limit the scope of work in order to release the app in an iterative and timely manner. We proposed and implemented integration with the shipping & procurement provider in order to fully automate the order process.

Advanced payment integrations 

Robust infrastructure setup

Smooth takeover by the in-house team


Firestore logo

Awards & press releases

"Quittercheck is the first nicotine cessation tool that gives an immediate consequence: If a user smokes/vapes/chews, they lose money. This is one of the reasons why it is so effective… because it taps into the fear of loss, a powerful deterrent."

How do we handle mobile app development?

Concept Exploration
Proof of Concept
Product Design
Agile Development
Maintenance and Support

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Meet our expert

Let's schedule a 20 minute talk

Łukasz Kosman, Co-founder and CEO at LeanCode

This is the initial scoping call. Its purpose is to get a better understanding of what you want to build. After this call, you will have an idea about your project's feasibility and the ballpark estimates.

Łukasz KosmanCEO at LeanCode