Pay Per Minute

Is it worth to launch

a new service?

Expert consultants now charge for their professional phone calls.

Driving the project from an Android mobile application to a unique, hassle-free service.





Project type

Product Design






Pay Per Minute

Charge business phone calls

Pay Per Minute is an Android mobile application that helps expert consultants and entertainers bill their professional phone calls with customers.

As the product designer I worked with the Minutizer team, my client, and Adonis Software, the developer, to design the M. V. E. for one of their innovative services.

the team & my role








Pay Per Minute is a simple mobile app that empowers consultants to charge for offering their expert service via phone.


Think PayPal for time.
Minutizer started as a payments system for live interactions on  Skype.

short brief

While traveling to conferences across Europe and US, clients and partners suggested that an expansion of Minutizer’s services into phone call billing would be highly welcomed.

This was in line with Minutizer’s product strategy. Launching a new service could lead to a new revenue stream, but being the first on a new market is not always easy.


The Pay Per Minute app, mainly an M.V.E. , would help evaluate with a decent cost this opportunity and determine if it makes sense to invest into a larger scale solution that requires ongoing maintenance and dedicated support resources.

Launching a new service could lead to a new revenue stream, but being the first on a new market is not always a comfortable position.



what are we trying to do here?

for the business

Testing a new service that would allow Minutizer to expand their offering. In line with the brand vision allowing them to get the necessary intel to develop a sustainable new revenue stream.

for the customers

Make it easier for current customers to charge for the extra time spend with clients offering services via phone. Allowing others to offer more by consulting or entertaining using their voice.



There was no visible market at the time for such a service. The benefit was sailing on a pretty blue ocean, but being pioneers meant we had plenty of exploration and hurdles ahead.

This was my first direct collaboration as a freelance consultant with a remote development team and the first time a client would trust me to take over, leading the efforts as a Project Manager.


the design journey

1 week

Why are we doing this?

My collaboration with Minutizer spread across 3 years, I was familiar with their product. But this was a new market so my first question was: who’s our competition?

I began with individual interviews with the CEO and CTO to gather the vision and expectations regarding the product and make sure it’s feasible from a tech perspective with the current setup.

Looking for inspiration and direct competitors, what I could find were at best apps that relied on a built in VoIP service that could be used as a reference for charging.

User research was informed by tens of support requests gathered by the customer experience team and private live chats at two of the events that I attended, along with the marketing team.

2 weeks

How will we do it?

So whom were we going to serve? What would we offer that actually helps them?

It turns out that our customer was the one that was already charging for phone consulting, albeit in a less precise or comfortable manner. They would give our solution a solid shot.

The app was not going to be actively promoted. Only a couple of hundreds of users would use it, a very small percent of Minutizer’s pool of clients.

Our intent was to get as much intel as we could about user’s needs, expectations, use cases and behaviors. We could not have done that without an actual working service.

This translated into developing an Android app that would be able to track the duration of incoming calls from specific phone numbers while logging and charging would be handled by the already existing backend.

4 weeks

What should we deliver?

After three iterations we clarified the basic flows and set of features we would provide the users with.

There were plenty of questions to answer:

– what do we show, when and how?
– how visible should the app be without bothering the user?
– where’s the right balance between scope and quality?


Finding a developer willing to take on the challenge of logging calls on Android was not easy. Trying to minimize project costs led us to consider enlisting the services of a freelance developer.

There were 3 weeks with no visible progress. We had to move the needle, so we went back to looking for a safer solution, with an increased budget. In the meantime I proceeded with sketching the main screens of the application to validate main content items.

After weeks of searching, the negotiations with a brave development company were going well and I went ahead and shared the specifications that were clear, up to that point. We had a kickoff meeting and agreed on a development calendar.

The initial estimate meant that the app would be ready to launch within 3 months. We had the developer onboard so I proceeded with validating the wireframes with the whole team.

Reaching consensus, they started developing a skeleton for the app based on the wireframes and also the research regarding hooking onto incoming and outgoing phone and Skype calls, in order to log them and track their duration.

Having received validation from all the stakeholders (now including a tech representative from the developer) I proceeded with the visual design of the interface.

Device mobile
2 weeks

Does it work?

I remained in the project to oversee the implementation of the app and also acted as a second layer of QA, on behalf of my client. Managing a project with technical conundrums is not a comfortable role. It wasn’t easy to to balance expectations and patience to reach the merry end.

A group of 10 beta testers were the core source for feedback and input on how to improve both the application and the service on the whole. After one month of active contact, the customer experience department took over communication and monitoring.


what we brought to life

Towards the end of the fall we published the first stable RC (release candidate) and in December, after ~6 weeks of iterations we had a solution that covered most of our initial goals.

Over 2018 we would monitor the KPIs we set during the strategy step and launch the current service, which doesn’t involve any app installed.

track incoming phone calls

Our top priority: track incoming caller and the duration of the call

log all the professional calls

Logging all the calls, including missed and rejected ones to allow doe follow-ups.

review calls and transactions

Access to logs of the last 100 calls made via phone & Skype

receive system notifications

Another channel of communication between the user and the system.

DESIGN Duration

9 weeks

design budget interval

5 ↗ 10K EUR


still curious, eh?

You can give it a go, it’s still available for download and install,

but keep in mind it’s not a supported product.


drawing the line



The MVE stage was live a little over one year. It was meant to gauge needs, expectations, surface user behavior.

Hoping for 500 clients and reaching over 1000 installs, encouraging  feedback from customers and the valuable insights drawn from this experiment led to Minutizer’s expansion of its offering to phone call charging with no strings attached.

Guess what? Now you do not need to install an application on your phone!. Also your phone number and the one of the caller remain private.


While it seemed like a small project at first, the actual development took well over the initial 3 months. This made me set a flag in mind when it comes to estimations for projects that involve pushing the limits of tech.


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