To my surprise, apples are pretty resilient. Initially heated it up in the oven at lowest temperature for about an hour and left it to the elements, hoping that it would dehydrate. Not really, it would take a lot of time. Then took the help of internet and found that apples can be cooked (in my defense, growing up in India, apple pie was never a dessert for us and it didn't cross my mind that I can cook it). So finally cooked it about 350 degrees for about an hour and as soon as it opened up cracking, left overnight on the counter top. It did the trick.