We had to check the stored apples regularly and any that were deteriorating were removed and used immediately - maybe stewed to eat with our morning porridge.One thing we never made - but I am certain that we would have done if we had known that you could - was fruit leather.
Cook the apple until soft and then leave to cool - it needs to be put through a food processor/liquidiser, and if you do this when still very hot then it may splash out through the lid.Process until smooth and there are no big bits of peel left.If you don't have a processor then just push the pulp through a sieve, you probably won't be able to sieve all of it but do your best.
Now, I have a dehydrator, and because it is for work, I got the biggest I could find. It has nine oblong trays and I have never regretted buying it. The one I have is probably a bit over-sized for most homes but there are plenty of smaller ones to choose from. I spread the pulp onto silicon paper in a thick layer and then set the timer for about 8 hours. Follow the instructions with your own machine. You can also put the paper onto baking trays and place in the oven on the lowest possible setting. Leave over night and assess in the morning whether or not the leather is dry enough or needs a little longer. Funnily enough, it will be like leather! It will easily peel away from the paper and I then roll it up like a swiss roll, before slicing across ready for storing. I keep some in a clip top jar for the grand children when they visit.
That is the miracle of food preservation.