This app allows the technician direct access to the principal component and spare part information via smartphone. Whether price or information about usage, the predecessor or successor of the respective component, or downloading technical documents: everything is communicated immediately after inputting the material number or using barcode recognition. If the order number for the main product is entered then a list of all the associated components is automatically provided. This quickly and easily gives the technician a complete overview. The app is easy, quick and convenient to operate. The user is assisted with the operation by means of text-based help. The Viessmann spare parts app offers the following functions: - Barcode scanner for convenient reading of Viessmann spare part barcodes using the smartphone camera function - Spare part searching by material number or full-text search - Detailed information about spare parts and assemblies, e.g. such as price - Usage check for a spare part or assembly - Compatibility check for a spare part or assembly with a basic unit - Predecessor and successor search - Downloading technical documents in PDF format