I cannot grow apples here but lets talk of fruit trees in general. Generally speaking one should thin the fruit because most fruit trees produce more fruit that the tree can sustain. This is done to make the remaining fruit a better larger fruit. But, in your case we are talking about a young small tree not a full grown one. I personally have done both on my trees. I have peaches, pears and figs. The prevailing thoughts are that when one removes the fruit the tree will use its energy into making more roots limbs and foliage. This may or may not be true, because, how would you know for sure? Personally I don't think it matters. I do know that the first fruits of a young tree are not exactly what the fruits will be in another year or two. They aren't as large are as sweet as they will be as the tree gets bigger. I would just let your 2 apples grow and enjoy them. Next year will be a lot better but still not what the tree will do 3 or 4 years down the road.
