You don't say where you are in the country. The green leaves on your tree pictured are turned back which suggests water lack. I have ten trees on limiting root stock in a planted border. The newer ones have their 2 litre Coke bottle and get a regular top up. If a fruit tree is in distress through water shortage it is probably more vulnerable to attack by all the nasties that lurk to have a go at your trees. When we had an orchard we kept the grass away from the foot of the trees so we could easily feed and water them.

Agree with Dorjac's comments, particularly about keeping the grass away from the base of the trees. Does look like drought and mildew has set in as the leaves died back, but you say it happened last year too - at the same time of year? And were you in drought this time last year too? Without knowing where you are, we can't guess whether this might be the problem or not.

it could be insect rather than fungus . it mite be worth opening the leaves up and having a look that is if it isnt a watering problem .

i would of thaught drought would make the hole tree generaly go brown but that doesnt seam to be thecase here as i see good leaves and young apples right next to the dead ones . if its not watering it mite be worth showing someone in your local garden centre maybe .