Spoiler 6 1/2 apples if the center apple is a whole apple. If it is half apple and it appears full due to aerial view, then the correct answer is 6.
@anjalin and @Marun, Have you considered the option of the center apple being half or full? It is an aerial view and it looks like this apple is at a lower level to me and there is a possibility that it could be half apple. Logically, there are no full apples in this and therefore, it is a good chance it is just half an apple cut across in the middle.
Ok that you rejoice & delight. Share your method of discovery in Spoiler. There lies our entertainment and or enjoyment!
I expect few more would visit and play. Lalit, Anjelin & swarna mary sisters & viswa Sir are finally with perfect answer.