Has anyone tried using inscape online app rather than downloading the program? I thought it might save some hard drive space but not sure it will work as well. I am hoping to be able to vectorize a few things to use in logos.

Are you really that short of drive space? If so you need to be thinking about some sort of increase.

Have you considered the portable version of Inkscape. It might run off a usb drive although bound to be slow or you could move on/off HDD as required.

There are smaller applications, but you are better off with a more comprehensive program such as Inkscape, it is easier to use.

An example, GLIPSgraffiti, a java application, only 10 MB. Big-However, if you do not have java installed add another 90 MB for the java runtime. Then in use, squares, circles, not too difficult but drawing a bezier is a PITA.

All that is creating from scratch, if you are hoping to vectorise a raster graphic, this is not always a wonderful way to go. Thousands of nodes where a handful will do, colour banding in place of gradients.
Also there are online convertors for raster-to-vector, no need for an installation. That is another option.

Thank you for your input...I think an online converter would be the best way to go.