Frisian houses, dune grass and smartphones: 123onsite builds on the island of Sylt

Founded in 1930 by Edlef Jensen, the construction company Edlef Jensen GmbH has been active on the North Sea island of Sylt since the 1970s. Basically, the construction specialists does it all: from concrete and reinforced concrete work, to masonry and carpentry work, to renovations for private, commercial and public clients. While the nordic company’s focus was on new buildings just a few years ago, one third of its orders are now conversions of existing buildings. While the Nordic company’s focus was on new buildings just a few years ago, one third of its orders are now conversions of existing buildings. With up to three levels, which are used as a parking garage and swimming pool, the construction company builds a basement under the mostly luxurious vacation homes.

10 users have tested 123onsite


In order to declare war on paperwork and to make data available without media discontinuity, the search was on for an appropriate software for construction site management. And in the end they found 123onsite.


After researching the market and visiting the leading trade fair BAU, the decision to test 123onsites was made fairly quickly and ten employees of the Sylt-based construction company were selected. After completing a training course on how to use the app, the employees thoroughly tested it over a period of three months. Within a very short time, they were so impressed that the decision was made to equip all the remaining columns with smartphones and, of course, the 123onsite app.

Lars Volquardsen Geschäftsführer der Edlef Jensen GmbH
Edlef Jensen GmbH Logo

Lars Volquardsen

Managing director and site manager

Initially, colleagues were a bit skeptical. But they quickly realized that entering hours via app is more convenient than filling out timesheets manually.

Edlef Jensen GmbH

Construction company

Practical functionalities for the construction sites on Sylt


What is it exactly that made Edlef Jensen GmbH choose 123onsite? 123onsite is a software that can be used both on the smartphone and as a desktop application. The software core is located on a server within the company or in an external data center – this decision has been left to the Sylt-based company. And you, too, of course.


Through the smartphone app, Jensen GmbH employees collect project information directly on site at the construction site. The transfer to the Office version is encrypted and automated in the background. Even if there is a dead zone on the construction site, the craftsman records the data offline. Once reception is restored, the collected data is automatically transferred to the server.

Zwei Bauarbeiter der Edlef Jensen GmbH auf der Baustelle, mit einem Handy in der Hand

Edlef Jensen GmbH now saves both time and money


Today, employees log into 123onsites in the morning, sign in at the construction site, and then book their attendance time. The data entered is transferred to a server in real time, so that everything is immediately available to the company office in digital form. This makes it easy to build smarter on Sylt now too!

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Image credits: 123onsite/Timo Lutz Advertising Photography.