Are there any significant differences between the Audi A3 and the A4?

I am in the market for a new car and am considering both the Audi A3 and A4. Aside from the obvious size difference, are there any significant technical differences between the two models that I should be aware of?

While both the A3 and A4 offer similar interior features and performance, the A4 has a slightly more powerful engine and upgraded suspension. If you prioritize performance and handling, the A4 would be the better choice.