How not to make the next useless app. A brief guide to Customer Development
6 min readMay 31, 2019


Before you start building a new product, make sure that it is not useless.

Imagine that you are a novice entrepreneur. Yesterday you had a brilliant idea — to make an application that offers a random movie for the evening. You wrote on the paper the advantages of the product, drew a mockup, and received support from friends: “Great idea! I would love to use such an app.” Your mother says to relatives that this is the best idea she has ever heard.

You subscribe to popular blogs that explain how to build products, hire a developer, a designer, and create a disruptive application for half a year. The day of release is coming. You are proud to publish an App Store link in social media and waiting for a wave of installs. But nothing. Days go by, and besides your mom, sister, and several teenagers somewhere in the south of Chile, nobody downloaded the application. Another month passes — the situation does not change. Tens of thousands of dollars that you invested in the development, burned along with your dreams of a successful product.

The problem that you made a leap of faith without any testing. Before the development, you didn’t check whether someone needs random films suggestions. Perhaps people are more inclined to choose a film on the recommendations of friends.

This situation is a classic trap that too self-confident entrepreneurs fall into. The belief that they understand users well plays not on their side. Customer Development helps to avoid it. It’s a simple but possibly the most important tool for any product development.

What is Customer Development?

Customer Development is the testing of an idea or a prototype of a future product on potential consumers. This term was introduced by serial entrepreneur Steve Blank. In other words, it is direct communication with future users to understand their needs better.

In real, building a product is much easier when you and a team understand who will use it, how and why. It all comes down to audience research: the conditions in which your user is in, what worries him, why he is looking for your solution, and why (in his eyes) it looks better than competitors. The best way to conduct CustDev is to talk to the user about what he cares about, what problems he is experiencing, how he is trying to solve them. So, a good CustDev is scouting, which determines the reasons why the user is willing to pay you money for the solution.

Why do we need it?

Building a product without researching the problems of an audience is big nonsense and unfortunately a very common misconception. Investigating demand is always cheaper than writing code right away. Tritely need fewer resources and money.

The biggest mistake is to measure the pain of users according to your personal feelings. If you don’t understand something, it does not mean that it’s impossible. One of my friends works for a company that makes an app for rappers. And this is what he said: “It’s hard for me to imagine people who are willing to quit their jobs to read rap. But here I found out that such people exist. And this is quite a big auditory.”

A successful product can be built without CustDev. But not immediately, with much more money, and if you’re fortunate.

How to do Customer Development

Audience research begins with segmentation. You need to identify the users with whom you plan to communicate, not on a demographic basis, but a role basis. Not “girls 20–25 years old”, but “people who are interested in movies and free in the evenings.” Then different segments need to be prioritized according to such factors:

  • reach — can you find them;
  • volume — a subjective assessment of the number of users in the segment;
  • satisfaction — how much your decision will help them.

For large-scale research, you need to use ad tools. But the easiest way is to find potential users among friends or friends of friends.

“If at the beginning you don’t understand how to find your potential users — think about how you will do it later, when the product will be ready.”

When you have identified potential users, arrange an interview with them. It will be great if you talk in person. If it does not work out — arrange a call or write in the messenger. At least 5 interviews should be conducted for each type of user.

Interviews should not look formal and fake. Communicate with them as a friend. For example, start a conversation with a discussion about your favorite games on PlayStation.

The most important rule of CustDevasking questions about the future is strictly prohibited. Ask users about past experiences. This technique is also called “The Mom Test” according to the book by Rob Fitzpatrick. It is a universal technique for user research.

How not to ask questions:

  • Are you ready to pay regularly if we offer you a service for booking restaurant tables?
  • Would you use the function of an additional order of food?

How to ask questions:

  • How do you usually book a table in a restaurant? Have you been looking for booking services?
  • When was the last time you booked a table? Remember your emotions, what was happening, were you satisfied?

For a good interview, you need to prepare questions in advance and adapt them to each specific user. The interview takes ~60 minutes.

The second rule of CustDev — you can not sell the product to the person. Questions should be asked cleverly so that the person himself tells what motivates him to use your product. The worst thing that can happen during CustDev is that you start convincing the user that your product is better than its competitors. You are a researcher. Try to find as much new user information as possible.

Some additional tips:

  • Don’t pay people for interviews.
  • Don’t react to awkward pauses in the conversation — let the interviewer fill them.
  • Record the discussion on the recorder, to have everything recorded and not “invent” anything extra later.
  • Organize interview at that place, where a person uses your product: in his office, house, stadium, etc. Sometimes the environment can tell you more than a user.
  • Personal interviews are not suitable for all users. A lot of people are much more comfortable to chat.
  • Be ready that in research interviews, people tend to deceive and exaggerate.

At first glance, it may seem that CustDev requires tricky skills and secret technology. But in fact, this is an ordinary human conversation. Don’t try to build complex rules and processes. Just start chatting with people — the rest will happen.

How to work with results

The result of user research is insights (not obvious fragments of behavior). The resulting set of insights must be validated — to understand the priority of user problems. For this you can use services like SurveyMonkey or Google Forms. For example, you can ask users to rate the importance of a problem on a five-point scale.

Insights are best stored in the format of a portrait and quotations: describe the user and provide a fragment from his interview. For example, Thomas, 30 y.o., lives in California. “I use your product to… it pisses me off when… I constantly feel…”

You can collect the results in a spreadsheet (or slides) and use as a guide in product development. “Observing this behavior of the user, we believe that having made X, we will come to Y.” In this format, it is much easier to set tasks for the team and make reports to investors.

That’s all folks. I think several pages as for a brief guide to Customer Development is more than enough. If you need any consultation regarding this process — feel free to write me or my team for a free consultation. I will be happy to help you.

And the main thing to remember.

If you conducted CustDev and didn’t find any interest in your product — don’t be upset. It’s a shame if you built a rocket, invested a million, and failed. But if before the building, you understood that nobody needs the idea — this is pure joy.

Originally published at on May 31, 2019.



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