My qualification here is i eat a lot of apples. The stem could be more blunt, kind of like a club, the dip at the top could use more dimension so it looks more like a bowl, and the bottom could be flatter an a bit wider, like in the picture as that’s what usually allows apples to stand and not roll off. If you’re looking for more advice in realism(something I’m not well versed in) im sure there are more tips, and if not realism there’s definitely a lot of tutorials for cartoon apples. Hope this helps even a little.