content: I really like the Night Mode feature I sometimes suffer from Light Sensitivity Migraines  havin the feature to turn the background to Night Mode is the best option yet. I even use it on my Internet app when I have a minor migraine as well. I think that the change of the way you want to read a document in the settings is cool too. Ads dont bother me as long as they dont try to cover the docs Im tryin to read. I have the free version as I prefer it over the paid vers.