Tutorial on how to create infinite scroll with Rails @ jQuery, full post @ http://christianvarga.com/blog/2013/02/simple-infinite-scroll-with-rails-and-jquery/

_posts.html.haml

- posts.each do |post|
  .post
    = post.content

application.js

//= require jquery.inview.min.js

Gemfile

gem 'will_paginate', '~> 3.1.0'

index.html.haml

.posts
  = render :partial => 'shared/posts', :locals => { :posts => @posts }
= link_to 'Load More Posts', posts_path(:page => @posts.next_page), :class => 'load-more-posts', :remote => true if @posts.next_page

index.js.haml

$('.posts').append('#{escape_javascript(render partial: "shared/posts", :locals => { :posts => @posts })}');
$('a.load-more-posts').attr('href', '#{posts_path page: @posts.next_page}');

- unless @posts.next_page
  $('a.load-more-posts').remove();

post.rb

class Post < ActiveRecord::Base
  ...
  self.per_page = 10
  ...
end

posts.js.coffee

# if you aren't using turbolinks, replace the following line with `$ ->`
$(document).on 'turbolinks:load', ->
  loading_posts = false
  $('a.load-more-posts').on 'inview', (e, visible) ->
    return if loading_posts or not visible
    loading_posts = true
    
    $.getScript $(this).attr('href'), ->
      loading_posts = false

posts_controller.rb

class PostsController < ApplicationController
  def index
    @posts = Post.paginate(:page => params[:page]) # replaces Post.all
    respond_to do |format|
      format.html
      format.js # add this line for your js template
    end
  end
  
  def home
    @posts = Post.where(:user_id => current_user.id).paginate(:page => params[:page])
    ...
  end
  
  ...
  
end