Sweet Home 3D is great if you don't want to download anything, since they have a browser version.

My app improves on Sweet Home 3D in 2 main ways:

- Rearrange furniture directly in 3D (In Sweet Home 3D, you have to add/move furniture in the 2D view, which then updates the 3D view)

- Better graphics (Sweet Home 3D doesn't have textures on most furniture)

Both good points. The split between 2D and 3D in Sweet Home 3D is quite awkward. It is possible to retexture furniture but I never bothered. I think between the better interface and better default furniture you may have something here.