How to distinguish between desktop browser dimension of 1024px from tablet browser dimension using jquery

Now this might sound awkward but the problem I am facing is that, I have some scroll based animation functions for desktop browser while other animation for tablet browsers. Now I want the functions to work on a desktop with dimension of 1024px. Later, I found that iPad also has a dimension of 1024px, now the thing is I dont want the javascript animation functions that are running in desktop with 1024 dimension, to run in the iPad as the layout for the iPad is quite different and animations are also different. How do I create that distinction between Desktop 1024px and iPad 1024 px using jquery ? What advice can you give me regarding this problem ? Thanks for your reply. If you need a simulation of the problem please let me know. Sorry for the bad english.