Many of you know leather is a strong material, and when maintained correctly, it has a very long life expectancy.
Leather is known to be non-allergenic. All dust particles can be fully removed which makes it ideal for people with sensitivity to this type of allergens.
Leather is a natural material. It breather and has a natural elasticity. Minor color changes, porous defects and discrepancies on surfaces are not quality defects. They are part of the nature of the leather products. Leather can get stretched and "move" to conform to individual contours, yet still retains sufficient strength to provide support. Leather would get better with age. With regular use, its beauty deepens and its natural character becomes more intense. With appropriate care, it will last for years to come.
Perfumes and products alike may damage leather when applied directly. When the bags get wet, use a smooth fabric to wipe the water and leave it to dry. You may wan to polish the leather with a dry and clean cloth or soft and mild brush once a week. With this minimal care, your leather product will provide long-lasting use.
Things not to do...
With just couple of simple things you can increase the utility of your case:
o) Don't put adhesive stickers or glue which may permanently mark the case surface.
o) Don't over-stuff credit cards slots or money pockets. Doing so will stretch the leather.
o) Leather breathes, that's what keeps it soft and supple. Do not store the case in plastic bags. Cover your leather with breathable cloth, like cotton sheets when storing.
Remember, these are helpful tips, they will help you but can not provide 100% "solutions".