I can't say that I have any issues with apples, peel or not. And I eat them daily.

Is it a particular variety of apple that upsets your stomach, or do they all? If a sour variety doesn't agree with you, try a sweet one, and vice versa.

Liza, Eric had a good point there.  It's been  the MacIntosh Apples that I can digest without any issues. They are softer & sweeter & even though I live in the area of food growth industry we are in, MacIns. are hard to get after February.  I'd love some kind of unit in my home that stores foods like the refridgeration they receive on/ before the market. Does that make sense?? 

I peel Apples though as even in making my own apple sauce, the skins always need to be removed before jarring & they go through a lot of heat not to be broken down into apple sauce in the first place.  I peel all my veggies,  especially  if I'm eating them raw. Even those lovely sweet Red Peppers!  Lettuce tends to have long strands of hard to digest pieces too. This allows me to enjoy a plate of Greek Salad,  if you want to make a meal of a Greek Salad, try putting a grain of some kind under the veggies & enjoy with a protien if need be or maybe some crispy fried Tofu.  

Between  🌶 Red Peppers & 🥒 Cukes & 🍎 Apples, I think they all prove challenging for digestion. Potatoe skins too.  I've seen skin from them all come down the digestion channel a good week or so later no matter how well chewed they are. Fruit & veggie skins are tough customers so be careful.  Same as 🌽 Corn,  but small bites of corn on the Cob eaten with 🥔  potatoes  has made being able to enjoy a small Cob possible in summer & who can resist the sweetness of corn on the Cob! Lol! Even if you nervously eat corn on the Cob & spit out the well chewed corn kernel skins, at least you had a chance to enjoy the sweet taste of Summer . 

I am always careful about any fruit & veggie  skins that might get stuck where scar tissue has formed & tightness from an Anastomosis has been made & cause a food traffic jam & in turn a blockage.  If in doubt, I leave it out is my motto. Lol! Plus drinking fluids with a meal really helps to aid in digestion. Where stomach acid meets acids in foods, dilute with extra fluids if you can.  

John... Hey, any update on how things are going for you?? I'm  not good at finding forums so I'm asking here,  I think of you & your family so often!! 🤷  The impact of a spouse having cancer when the home life is already challenged with Ostomies is not fun.  Looking back the other day  marking my Hubbies Heavenly B'day,   I do wish someone, anyone had asked me and even my kids how we were coping... deep sigh... .