Overall, the town as a whole was somewhat subdued after the trial. They knew that Bob Ewell was guilty, and they knew that race had kept them from making the right decision.
Jem was the most clearly affected. This moment marked the shattering of his child-like innocence. For the first time he experienced the hatred and brutality of man. In his mind, Tom was clearly innocent and he did not understand why the town did not see it that way as well. Knowing the Tom was innocent and that Atticus's defense was superior to the prosecution's, Jem was completely confident that Atticus would win the trial.
Tom was also affected. He lost all hope for appeal, and let the outcome of the trial dictate his actions in trying to escape, which lead to his death.
The outcome, though technically in Bob Ewell's favor, also destroyed what little reputation Bob had. This caused him to come after Atticus and the children, seeking revenge on Atticus for ruining him in the town's eyes.
Lastly, there was a positive reaction among the African American community. Though Atticus lost the case, they recognized the amount of time and effort that Atticus put in, and they knew that it was not Atticus's fault that the case was lost. They brought him and his family food in order to show their gratitude towards him.