Android : How to prepare your Main activity and load all contents Properly without causing (slow loading) : I'm still new to java and android so i'm asking these kind of questions here to understand how it should works .

if i have 2 Activities in my app 

    Welcome_Activity.java and Content_Activity.java

usually the First Activity will work smoothly 

but here the problem comes , when the Content_Activity starts 

first thing will be called is :

    onCreate

which has so many things to prepare the Page for the user.

this always causing slow start on my apps

how can i get rid of this ?

i need ideas to do that properly 