I wanted to know if I should apply on August 1st with my current mcat score or wait until I retake it. I got an 18 which is extremely low. I have a cgpa of 3.1 and sgpa 2.8.
I wouldn't apply now or even apply now indicating that you will retake it.
Here is why. If you are going to retake it, then what is the point of applying now? You will have no benefit because the school will either reject you outright or they will invite you to an interview. Now at the interview, the 18 on the MCAT will come up and what is your defense? That you will retake it? It is much better to have retaken the MCAT and gotten a higher score and then say "Oh yeah I got an 18 the first time but the second time I got a " insert higher than 18 score." at the interview.
In addition, I am not sure if the application service will send updated MCAT scores to the schools after you submit the application. I know they will send in your fall grades but I don't know about MCAT so you may have to resend the MCAT yourself!
And, the schools that are considering you due to MCAT will set your file aside. Lets just say that your file will have a good chance of getting lost or overlooked.
You have one chance to impress the school so why not do it with your best foot forward?
Also, Pod school app is not like Med school app where time of application is very important. Most people turn in their app around nov-feb.
So sign up for the MCAT for this fall and study all summer, aim for a 22+ and then turn in your application.