AllTrails is a great resource and phone application that contains tons of hikes. One of the features of the Pro version is it allows you to download maps for use when you're offline, which is literally a life saver to help you from getting lost. Our friends over there have hooked us up with an exclusive list of the top 52 trails in all 50 states, download it here or view it on our Google Drive here! No more researching for hours to find a good trail with this list and their app containing all the information you need to get going quickly. Just be sure to download the maps while you still have cell phone reception.   
http://alltrails.com