We had the opportunity to interview Uwe Trottmann, creator and principal contributor of the app SeriesGuide with over 1 Million downloads on Google Play. 

Uwe Trottmann

Uwe Trottmann

Small Business Owner at SeriesGuide

He received his M.Sc. Computer Science at TU Munich in 2013 and is interested in making software usable for everyone. If at all, he is only looking for part time work next to his other endeavors.

Download SeriesGuide!

Dorian: For how long have you been coding?

Uwe: That’s a very good question. I started in school in 2004 because a friend of mine coded a basic vocabulary training program in Visual Basic. I started to improve that program and later enrolled in a programming class in school, which was very new at the time. Right now it’s common to have computer science classes in school, but back then it was not the standard. I started doing other side projects for fun, but only got serious about coding when I started studying computer science at University in 2008.

Dorian: Do you think going to University helped your projects?

Uwe: Yes, absolutely. There’s a lot of technical and theoretical background that you are not exposed to, if you just program. At University, the coding exercises were very easy for me, because I had a lot of practice beforehand. However, I learned so much about other things like designing systems, Software Engineering, how to manage projects. Also the theoretical background, like data structures, how to do things efficiently. Also things I never would have looked at, like computer architecture, how stuff works on the lower levels, etc. Which is interesting to know, but it doesn’t really help with the stuff I am currently working on. 

Dorian: But that knowledge of the lower levels has maybe helped you solve some bugs?

Uwe: It has a little bit. I think the only relevant thing that I still come across now is bit operations. But things like registers, or programming in assembler, no. This is probably more helpful for the C guys, which program at a lower level. I like working at a higher level. So I program in Java, Kotlin, for Android, and Windows back in the day. These all abstract the lower level away and I didn’t have to worry about memory management, which I didn’t really like doing back then. It’s complicated and very easy to get wrong. I don’t know if you have heard about pointers, but they are one of the biggest problems with programming in C. If you get a pointer wrong everything breaks, you have security issues, and so on. If you talk to C developers about pointers, they could go on forever.

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Uwe Trottmann at Droidcon Berlin 2018.

Dorian:  How did you start up with Open Source? Did you start right away out of University or did you do work for other companies and do Open Source on the side?

Uwe: In the beginning I had my own projects and didn’t know about Open Source. The first thing that I open sourced was SeriesGuide. My work on SeriesGuide started as a hobby because I had recently switched to Android and was missing the series management app I previously used on another platform. I first posted SeriesGuide to Google Code and then the Google Play Store in 2010. I later moved it to GitHub 2011. My work got more serious during my computer science studies at University. Once I started using GitHub, I added more libraries that SeriesGuide uses and I contributed to other projects on there as well. GitHub really accelerated the SeriesGuide development.

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SeriesGuide Statistics Screen

Dorian: Did having access to other Open Source projects help you develop SeriesGuide?

Uwe: Of course, it tremendously helped. I guess SeriesGuide is probably 80% other libraries, it’s Open Source so you can go check. Some of the API integration with the TV show database I used back in the day was an Open Source library, so I built on top of that. I then replaced it with my own later. Also if you know Jake Wharton, the Keynote speaker for Droidcon Berlin this year, he was one of the early contributors to SeriesGuide and I used some of his libraries in the beginning like ActionBarSherlock. Then later the networking and logging libraries he was working on. Obviously I used the Android Open Source libraries once they came along. SeriesGuide would not exist without Open Source software.

Dorian: Why did you choose Open Source as the foundation for your paid app?

Uwe: It started as free and Open Source at the beginning on the Google Play Store, because I was just a computer science student and didn’t have the need to make money. It was also rather complicated to charge money, because you have to set up your own company. Around three years after I posted it to the Play Store, due to people suggesting that I charge money, I started developing extra paid features, such as notifications, theming, and then later the syncing component.

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Shows on SeriesGuide

Dorian: Is the core of your project still Open Source and will it stay like this forever?

Uwe: The whole app besides the small server component is public domain. And the spec for the server component is open, so you could build your own if you wanted to.

Dorian: What is the best thing about SeriesGuide?

Uwe: Honestly, I’d have to say the community. Back in the day I had a few people who really pushed me to improve the app, like Jake Wharton, Craig, Chris, and other friends. They really helped me get SeriesGuide off the ground. Without them I would have fixed a bug or two, and then would have moved on. Because of the continuous requests and a growing community, I had to keep going and make it better. And without the community paying for the app, I wouldn’t have the means necessary to continue working on it.

Dorian: What do you dislike about Open Source?

Uwe: Honestly, in the beginning I thought open sourcing would be risky because someone could copy my app, slightly modify it and then publish it, taking credit for my hard work. Because of that I have a separate private repository with new features that I hold off publishing for a few days. But if I remember correctly, this only happened once and was not an issue because the developer didn’t continue development. I am not 100% certain it was a copy, but the code looked very similar to mine. Right now, I don’t think this is an issue anymore. If people use my app they expect my updates because I maintain the app. If somebody copies it, they don’t have my work power and knowledge.

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Uwe’s contribution to SeriesGuide on GitHub as of July 6th, 2018.

Dorian: How do you manage your time between developing Open Source projects and your work?

Uwe: I work Mondays and Tuesdays on my main job, kind of as a backup. The rest of the week whenever I have time, I work on SeriesGuide and related Open Source projects. Of course it never ends up being three days. If somebody wants to contribute, I welcome pull requests. I also allow people to translate the app into their language. If somebody has a bug to report, the easiest way to do that is on the website. If people want to contribute code, they can go to the GitHub contribute file which lists everything you need to know.

Dorian: Do you have more features in mind right now?

Uwe: There’s a feedback site where people can request changes, and there’s no shortage of suggestions! I also have ideas in mind, but some things are bigger and I don’t want to do them right away. It’s a constant struggle to get things done. I am not out of ideas; it’s more of a time problem right now.

Dorian: You have a very good time structure, which is encouraging. How hard is it to turn an Open Source project into a profitable business? How did the community react that you have built a business with paid features on top of an Open Source project?

Uwe: The overall reaction was positive. Obviously there are some people that aren’t happy with the presence of paid features. I always tell them that the app has no ads in the free version and you can do pretty much everything except for some convenience features. I would say that for most people this is not an issue because the basic functionality of the app is still freely available. One of the early complaints was that I charge too much money. So in the beginning I was charging 1€ as a one time payment for all access, then increased prices to 3€ per year or a 7€ one time payment. I explained this was to support myself and future updates, basically development time, and most people understood that. I clearly mention that inside the app, paying is not only to get some features but also to support me and future updates. So far most people like the idea and buy into it. Obviously, if you look at the share of paid vs free users it’s nowhere near something like 50/50, it’s way less. But I have a core set of users who believe in the app and support it financially. So far this method has gone well. I am also pushing people towards subscriptions now to secure future development.

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SeriesGuide X Pass

Dorian: Do you think the complaints came mostly during the shift from free to some paid features?

Uwe: Yes. In the beginning some people were upset, but as I only made convenience features paid, it wasn’t a huge issue. That is also a takeaway for me: don’t have a free app and then suddenly make half of the features paid, because then users will get upset. I was very careful to only make new or some convenience features paid. Or when I made the previously free theming features paid, I made an effort to spruce them up before. But features like notifications and server syncing were new and weren’t available for free before I implemented them.

Dorian: Do you have any tips for developers that are starting with their Open Source projects or are thinking about open sourcing their code?

Uwe: The best thing you can do for your project is to Open Source it, or in short: put it on GitHub. If you don’t put it online, people won’t find it. Another good way to get traction is to contribute to other projects so people know you exist. And then if you ask for help or feedback about their library you are using in your project, people will get to know your project and maybe look at it. Contributing is a good way to get into the community and be noticed. Give and be given, right?

Dorian: Now we have some fun fact questions. First, what do you think about Microsoft’s acquisition of GitHub?

Uwe: I don’t really care, because Microsoft has done some great things for the Open Source community. Azure runs Linux now and they have their own Linux operating system. It’s still good to know that there is the Open Source alternative GitLab that people can switch to if needed. However, it’s sad that things get monopolized into those big companies. In the end, we are maybe going to end up with only Microsoft, Google and Amazon. GitHub sold out, but we’ll have to see what happens.

Dorian: Do you have a favorite book, film, or game?

Uwe: I’m currently reading the Expanse series, which is also on TV. But my favorite series is the Culture series from Iain M. Banks. That blew my mind. For TV, there’s so many options. I generally like science fiction. I recently watched Killjoys and Altered Carbon which were both really interesting. Star Wars Rogue One is my favorite recent movie. If you want to know what I’m watching, follow me on Trakt.tv, a tracking service similar to SeriesGuide, but web-based, that SeriesGuide also integrates with.

Thank you Uwe Trottmann for the interview, and thank you for reading! 

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We would like to point out that SeriesGuide is not affiliated with ObjectBox

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