Design software for laying out a home plan- Need a recommendation

[Jennifer Hollstein]

I am hoping someone can help me with a recommendation. In my past job I used 20/20 on a regular basis to draw up and layout kitchens, baths and any other room or even whole floor plans. I no longer have access to that program and do not have the thousands of dollars to buy it for myself. 

I am looking for an easy to use software that will allow me to walk into a home and draw it out and put dimensions in to give me that layout. 

Ideally it will also have flexibility to layer other walls so a new floor plan can be sketched over the original plan. If it worked on an iPad with a finger or computer pen that would be perfect. 

Does anyone have a recommendation for a free or Low cost software program that will allow this?

Thank you in advance.