How low is your low carb and what are your overall glucose levels and targets like?
Your sensor will tell you how you respond to apples, and eating them alone as a snack may give you different results to eating them as part of a meal.
I'll occasionally eat small portions of them without issue, usually as part of my meal, and this has little overall affect on my glucose levels.
But as you're in Crete, do you eat (Greek!!) olives? They are very low in carbs, and full of healthy fat and other "good ingredients"... and are definitely recommended as part of a low carb diet.