Flutter Mate


A dialer (VoIP mobile app) which serves as a free communication channel between recruitment consultants and Ukrainian citizens planning to work in Poland.

Project details

December 2020 - October 2021
Flutter, VoIP, SIP
Human Resources
Collaboration model
Time & Material
1 Project Manager, 1 Developer, 1 UI/UX Designer, 1 Manual Tester

Project timeline

2020 December

An organizational meeting to discuss the requirements provided by the client, followed by the verification of the proposed solution for communication, the layout of user paths and the app’s information architecture.

2021 January

Designing the visual aspects of the mobile application and choosing the right concept.

2021 February - May

Kick-off and start of the development process, including testing and implementation of Bisar dialer.

2021 June

Final tests and deployment in the Google Play store and App Store.

2021 July - October

Expanding the application by adding new functionalities.

About the application

Bisar is a dialer (VoIP mobile app) which does not require user registration and serves as a free communication channel between the Bisar S. A. call center, and Ukrainian citizens looking for employment in Poland. The need to develop such an application arouse from the lack of an accessible and convenient solution for Ukrainian citizens. Direct phone calls to the call center from the territory of Ukraine are too expensive, and the use of the Viber application, which is the most popular application in Ukraine, did not meet the company's expectations.



The main objective for our client was to verify whether their proposed communication method would meet the design objectives and guarantee the application continuity. Then, based on the requirements, the application with an interface ensuring free accessibility to users with varying degrees of technological skills was developed.

Mobile app
development process

1 Organisational meeting

The project started with a meeting to discuss the needs and goals of our client in detail. We went over the set of requirements for the application and the technological aspects. We also got to know the persona who the client wanted to reach with their application.

2 VoIP technology verification

Before we started to work on the design, our team assessed and tested the communication technology proposed by the client in order to make sure the investment was solidly grounded.

3 Product Design

Taking into account that one of the goals was to design an interface which is easy to use, we had to focus on the right layout of functionalities in the application and a user-friendly design.

A User Paths

Based on provided requirements, we designed the main and side user paths.

B Information architecture

We determined the main and the side user paths and then prepared the application view architecture.

C Lo-Fi

With the UI architecture prepared, the designer began to develop low-detail views.

D Lo-fi versions testing & selecting the best one

In order to make sure that the planned paths, architecture and views meet the specified criteria, we conducted two test iterations on potential users from the target group.

E Hi-Fi

We visually designed the tested concept in accordance with the current principles of brand’s visual identity.

F The client’s approval of the new design

The client received and approved the new design.

4 Mobile App Development

Having prepared all the necessary views, we began mobile application development.

A Assembling the development team

We assembled the development and testing team, taking into account the necessary competencies for the application production.

B An in-depth technical description of functionalities and roadmap

Considering the earlier verification of the technology and the prepared user flow, the developers re-planned the functionalities from a technical point of view, in order to eliminate the risk of postponing the development. Next, they prepared the final project roadmap.

C Starting the step-by-step development of functionalities

The app development began and the first features were implemented.

D Quality assurancee

We ensured quality by means of test scenarios and multiple manual tests conducted during the development process. The client was confident that the application would be bug-free.

E Approval and deployment

When all the functionalities were implemented and tested by our team, it was time for our client to approve the application and then deploy it to the Google Play and AppStore stores.

5 Maintenance

Following the app's successful reception, the client decided to further develop the dialer and together we implemented the feature of job notifications without the need to create a user account, grouping recipients by location and language.


A call made by a Ukrainian citizen using the Bisar application is forwarded to a VoIP PBX via the SIP protocol, and is then transferred to an available consultant.

Establishing such communication channel has increased the popularity of Bisar S. A. as a quick and easily accessible employment agency, which led to an increasing number of inquiries from Ukrainian citizens.

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