This is correct. Once you have a nice feature, you realize Apple's doesn't run everywhere. Marco is also correct about social. A simple commenting system and a

This is correct. Once you have a nice feature, you realize Apple's doesn't run everywhere. Marco is also correct about social. A simple commenting system and a highlighter and a red envelope would be useful. People want insightful quotes highlighted and commented, and want to be validated when people reply to their messages.