Quantum computing is a promising paradigm that offers reduced energy consumption, enhanced computational precision, and exponential speedups for certain problems compared to classical counterparts. However, manually building quantum applications that combine classical and quantum parts requires not only specialized knowledge in quantum computing but also significant programming expertise, creating a substantial barrier for many users. Classical low-code platforms can abstract away much of the coding effort, but they are typically domain-specific and not suitable for designing quantum algorithms. Moreover, simply reducing the amount of code is often insufficient, as developers still require a deep understanding of the underlying quantum concepts to model and implement quantum applications correctly. Therefore, it is equally important to provide abstractions that shield users from complex domain knowledge, allowing them to focus on the logical structure of their applications, regardless of their level of expertise in quantum computing. To address this gap, this work develops an open-source low-code modeling tool for designing quantum applications. The objective is to identify and define essential modeling constructs that provide higher-level abstractions, as well as lower-level modeling blocks that represent quantum gates, in order to support the development of quantum applications while ensuring accessibility for users with varying levels of expertise. The tool enables the modeling of both classical and quantum parts, allowing developers to build quantum applications. Additionally, the tool employs a standardized format for saving and loading models, ensuring portability and interoperability across different systems and platforms. The proposed concept will be implemented in a prototype and evaluated through use cases. In parallel, a low-code backend project will prototype the transformation of models into OpenQASM code based on the model structure and its standardized format.