What's your question? Ask

Sounds like apple cankers. This disease can not be cured. You can add more phosphorus and potassium to help with fruiting, but the disease will stay with the tree until it dies off.

This link will help you with a treatment plan.

http://ipm.ucanr.edu/PMG/PESTNOTES/pn7412.html

There are several diseases that can cause these symptoms. It can be difficult to diagnose without a photo- the best thing to do is to contact an extension office near you, since they will know what diseases are common in your area. Meanwhile, here are some resources you can refer to:
https://www.gardeningknowhow.com/edible/fruits/apples/apple-tree-diseases.htm
http://www.extension.umn.edu/garden/yard-garden/trees-shrubs/managing-apple-scab/
http://extension.psu.edu/plants/tree-fruit/diseases/apple-diseases

This collection of articles will tell you all that you need to know when growing apples: https://www.gardeningknowhow.com/edible/fruits/apples/

This amount can vary greatly depending on the temperature, and humidity,and many other factors. Generally, you will want to water when the soil is dry down to a depth of about 2 inches. Once it is dry passed this point, it will need to be watered, but can survive for just a little longer after this point.

As long as there is still a good portion of the tree still attached, they can usually recover from this kind of damage on their own. I would water once with a gallon of water, but replace 1/4 of the water with peroxide. This will help keep away an infection.

Your tree may not bear a full crop next year, but by the next, it should be producing well again.