Extremely Laggy RecyclerView Performance

I was having the same problem with RecyclerView. It was laggy. In my case, there was a horizontal list of image buttons inside RecyclerView.

I solved it by removing the scaleType from ImageButtons or ImageViews and loading images through Picasso with resizing like :

 Picasso.with(context).load(icon.get(position)).resize(270,270).centerCrop().into(holder.iconView);

The problem of lag may occur due to runtime scaling of big sized images or no. of images. It is not advisable. Whereas Picasso takes care of resizing, and loading efficiently. Also it handles caching for you.