BlueVary is a maintenance free gas analyzer for variable biotechnological applications. By selectable sensor cartridges different measuring tasks ranging from microbial, cell culture to monitoring of algae and biogas processes can be covered by just one device. The analyzer consists of a basis element with measurement places for two of the variable sensor cartridges. The third place holds a cartridge to compensate pressure and/or humidity. The integrated display ensures an overview about sensor and concentrations at any time. As already known from the forerunner analyzers BlueVary can be mounted on each fermenter from lab to production scale by using different mechanical connections without being limited by fermenter brand or manufacturer. Various data outputs are available. Annual maintenance is not necessary. In combination with the open software BlueVis the BlueVary turns into a versatile, effective tool for real-time online monitoring and optimization of bioprocesses of any kind.