Remedy for Tomato Plant
The light brown piece on the end of the tomato looks like it might have been part of the blossom. Cracking of tomato fruits can occur for several reasons. It could be due to high temperatures, too much soil moisture, or excess nitrogen. Also, some types of tomatoes are genetically more prone to cracking ('Cherokee Purple' is one type that is notorious for this). It could be due to any one or a combination of these factors. If it just one tomato, it is probably nothing to be too concerned about.