There are several architecture apps available for both professionals and enthusiasts that cater to various needs, including design, drafting, visualization, and project management.

1. Autodesk AutoCAD: AutoCAD is a widely used computer-aided design (CAD) software that allows architects to create precise 2D and 3D drawings. The AutoCAD mobile app allows users to view, edit, and share AutoCAD drawings on mobile devices.
2. SketchUp: SketchUp is a user-friendly 3D modeling software used by architects, designers, and artists to create, visualize, and communicate architectural designs. The SketchUp mobile app offers basic modeling capabilities and allows users to view and share SketchUp models on the go.
3. Morpholio Trace: Morpholio Trace is a digital sketching app designed for architects and designers. It enables users to sketch, annotate, and collaborate on architectural drawings and designs using layers, stencils, and tracing tools. The app also integrates with other design software such as AutoCAD and Adobe Creative Suite.
4. Adobe Photoshop Sketch: Adobe Photoshop Sketch is a drawing and painting app that architects can use to create digital sketches and concept drawings on mobile devices. The app offers a variety of brushes, pens, and pencils, as well as layers and blending modes for creative experimentation.
5. BIMx: BIMx is a mobile app developed by GRAPHISOFT for viewing interactive 3D building models created with ArchiCAD, a BIM (Building Information Modeling) software. BIMx allows architects, clients, and contractors to explore and navigate architectural designs in virtual reality (VR) or augmented reality (AR) environments.
6. Houzz: Houzz is a home design and remodeling app that offers a vast collection of interior and exterior design ideas, photos, and products. Architects can use Houzz to showcase their work, connect with clients, and find inspiration for their projects.

These are just a few examples of architecture apps available across various platforms, including iOS, Android, and desktop. Depending on your specific needs and preferences, you may find other apps that are better suited to your workflow and project requirements.