The story
behind GreenBill

From an idea to a business.

Ludwig Heer

CEO/ Founder

Ludwig is a chef, frequently present in german television shows, runs a chocolate manufacture, cooking courses and a restaurant. In his restaurant most of the workflows are digital already.

From booking a table, a paper-less kitchen monitoring, digital vouchers, IP-telephones down to digital logbooks of the company cars - everything is efficient and digital.

Everything? Everything except customer receipts.

Adding to the problem many suppliers of the restaurant still provide many of their receipts in the classic printed form, which creates extra efforts to get them digitalized.

Problem found and solved! This was the moment when Ludwig invented GreenBill. Since then he has been testing it in his own restaurant for more than 2 years.

Since this day Ludwig has focussed his energy completely on this new venture.

Our core team - fully dedicated to GreenBill

Niklas Karoly


Niklas has been the CTO of many Startups since his teenager years. His last venture was an IoT company focused on digital solutions for garbage management. Now he is our key developer and drives the further development of our services.

Giulia Siegel


Gulia Siegel is the girlfriend of Ludwig and takes care of all press and PR related topics at GreenBIll.

Veronika Kafl

Operations/ Customer Care

Veronika has expertise in banking and management. She the driving force in the daily operations of GreenBill. If you become a customer of GreenBill its very likely you will come in contact with her very soon.

Bernd Gruber

IT/ Server infrastructure

With his long term experience in developing in data base and web applications, Bernd was a key responsible person for creating the GreenBill software architecture.

Nikolaos Baltsios

COO/ Finance

Niklas has been a CTO for different startups since he was in his late teenager years. His last venture was an IoT-startup to digitalize garbage management. His expertise drives our technical development.

Our expert support team - all highly qualified experts in their field

Thomas Hielscher

Hardware/ Software Development

Thomas has been working for GreenBill since the first prototype was born. Making him kind the 'father' of our baby.


Sarah Schweizer


Sarah is our legal consultant, responsible for all legal and contract related issues as well as brand registration and IP management.

Philipp Sedlacek

Illustrations and Photography

Als freiberuflicher Grafiker und Fotograf kümmert sich Philipp um alle Print- und Foto-Themen von GreenBill.

Tech partner

Team B&W Engineering

Hardware/ Software Development

The company B&W Engineering covers a broad field of development expertise in both soft- and hardware topics. Together with B&W Engineering, GreenBill has developed and improved its unique hardware.

Consultant for data privacy


Data privacy

Data privacy is of highest importance for GreenBill. This is why we are continuously certified and consulted by the company DataGuard.