The main cause of foot skin problems is Athlete's foot.

These will be blisters with fluid in them that burst and peel. They hurt and burn. They are red. This fungus may heal up a little, but it remains in the deeper skin layers dormant and I believe it affects the nerves then even in that state.

The best treatment for it is Lamisil (Terbinafine ) cream. Use daily for 7 days, (14 days for severe cases) and it will heal up. Many Tinea Pedis organisms are resistant to the older antifungals, so choose Lamisil for best results.

Cracking skin on the feet is a sign of low Omega-3 status.
Taking flax oil, evening primrose and fish oil daily will help the skin be more supple and normal.

This link shows the various presentations of this fungus from mild dry looking skin to red raw outbreaks:
http://www.skinsight.com/teen/tineaP...hletesFoot.htm

Severe weeping lesions may become infected with bacteria, and then be much worse.

Soaking the feet now and then in epsom salts, and rubbing the dead skin off afterwards will soften dry skin on the feet as well.
People who only shower, and not take baths, will have dry skin left on the feet, commonly. Soaking in a tub removes the dry skin more effectively. Using harsh soaps that are detergent like Zest and Irish Spring, also defat the skin and make it more vulnerable to cracking.
Use unscented Dove instead.