I just submitted my UK tourist visa application and I inadvertently answered the question "The total amount of money you have for this trip" incorrectly. I answered 2000.36gbp, which should have been 2000gbp. At this moment I can't edit my application any more. What should I do?
You made an error on the visa application form and want to know how to handle it...
They like to think that errors fall in to several different categories. Based upon what you wrote, your computation was off by 36p. This falls in to the category of 'unintentional clerical error which would not affect the outcome'.
What that means is if the ECO saw the actual answer they would still make the same decision. You can contrast this with a case where someone who had a criminal history answered 'NO' to that question. That type of error can affect the outcome and so it is treated differently.
In a more general view, when I was doing applications for people, all the numbers were in whole units. Simple rounding is fine and ECO's are not going to be silly about trying to refuse somebody for rounding differences (doing so would violate the Wednesbury Principle and they can get into serious trouble for doing that).
Had your error been significant or would have affected the outcome, then your recommended course is to cancel the application prior to submitting your biometrics. But in the case you have described, it's not necessary to do anything.
Note: an alternative reference for the "Wednesbury Principle" as it occurs in English law can be examined here. There is a pamphlet that describes how perversity fits in with the other grounds for judicial review here.
Note: for an answer where the OP made a significant clerical error, see Standard Visitor visa application in The Philippines submitted with error