If you want a simple way to measure 2D objects and export CAD files with minimal extra drawing work, Flatify is a good option. Flatify lets you measure 2D objects and shapes by taking a photo of an object with a reference object, reviewing the photo, then selecting the dimensions of the reference object. It then converts those measurements into CAD files within the app, saving you time and effort.
For a more advanced solution that uses AI, Leo is a generative AI engineering design copilot that can turn text, sketches and specs into DFMA-optimized full-assembly 3D CAD models. Although it has other features like technical documentation and collaboration tools, it's a great tool for converting and optimizing designs for manufacturing and maintenance.
Although not designed for measuring 2D objects, EdrawMax is an online diagramming tool that can be useful for creating a variety of diagrams, including engineering designs. It can import a variety of file formats and has AI-assisted diagramming, so it can be used in a variety of industries and situations.