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Rent a 'donkey' with your mobile

Yet another Technical University of Denmark (DTU) start-up has seen the light of day. Donkey Republic has developed a kind of 'Uber' for bicycles. Meet one of the entrepreneurs behind the company

Donkey Republic has developed a—in principle—global bicycle rental service, among other things with support from a successful crowdfunding campaign. By means of a smart lock, which can be activated with a mobile phone and an app, you can easily find a rental bike in Copenhagen and pay the fee right away.

We have met former DTU student Jens Kjærby Frandsen—one of the entrepreneurs behind the start-up—at the Dare2mansion start-up co-working and incubation space in Copenhagen.

Why do you call your bike a ‘donkey’?


A bike is also called an ‘iron horse’ in Denmark, so we thought it would be fun to call our bike a ‘donkey’, mainly because a donkey is reliable and hard-working, even though it may not be quite as fast as a horse.”

How did you become a part of this adventure?

“We all come from different backgrounds and countries, but we do have one thing in common: We believe in the bike as a means of transport and its beneficial impact on society. It all began when we were trying to solve a practical problem: We wanted to give friends visiting us in Copenhagen the opportunity to go around the city by bike. It developed into a real project, and—with support from Innovation Fund Denmark—we developed a prototype of the electronics in cooperation with Delta (an approved technological service institute, ed.). This was when I became a part of the project.”


Donkey Republic has made bike rental flexible. With a smartphone and an app, you can easily rent and return a bike—independently of opening hours.

Photo: Donkey Republic

Why did you leave a secure, permanent job to be a part of a start-up?

“I have a BSc in IT from DTU and have worked for Oticon for eight years. During my studies at DTU, I got a basic knowledge of a lot of different things, including how to turn ideas into reality and solve problems. Combined with my work experience, it provided me with a good basis for bringing specific projects to life. And that’s a very useful skill to have when you’re starting a business. In terms of my career, the timing of the project was ideal, as I had reached a point where I was ready to change my way of working and my approach to working life in general. And I really appreciate to be in constant dialogue with the users. There’s always something we have to adjust, and preferably sooner than later. It’s not only a huge challenge, but also a great responsibility ... and both frightening and extremely satisfactory at the same time!”


A smartphone app gives you access to 24/7 bike rental in Copenhagen. The app shows the location of the nearest bike, unlocks it and also takes care of paying the fee when you drop it off.

What technical challenges have you had?

“As technical manager, I’m responsible for the technical aspects, that is, in short, mechanics, electronics, and firmware.  And we have two developers working with our two apps. One of our main challenges was to make a lock with a low power consumption. A donkey’s battery must be able to last up to 500 days, but this was difficult to achieve!

Another challenge was the connection between the lock and a smartphone. Our locks are based on state-of-the-art Bluetooth technology. It has to work the first time you activate it. The app must always be able to send a message to the lock to check whether it’s locked ... but again, it’s a function that eats into battery life.

The third challenge was Internet access. You need a smartphone to be able to unlock the bike. We have just launched an offline version of the system, so you only need Internet access once before you pick up a bike and once after you have returned it. This makes it easier for tourists to use the bike rental service.

The fourth challenge was some initial localization problems, when we were trying to make Bluetooth, GPS, and Wi-Fi work reliably at the same time. We have improved that with our new app by simplifying the system, so you don’t need neither GPS nor Wi-Fi to unlock the bike.

We needed a simple system that never fails. The simpler the system, the smaller the risk that something doesn't work. It has to be as reliable as possible, and we therefore test all the locks at Dare2mansion before they leave the house.”

Where can you find a donkey?

To start with, it was mainly in Copenhagen, but we’re now increasingly focusing on the global market. In the autumn—following a successful crowdfunding campaign—we sold the system in both Europe, the USA, Asia, Australia, and New Zealand. We’re ready to deliver to these markets this spring.”

See more on donkey.bike

Find more information on the Technical University of Denmark