I use an app that backs up all my SMS/MMS onto Gmail (SMS Backup+). It labels them accordingly and separates them by contact. The downside is that MMS are put o

I use an app that backs up all my SMS/MMS onto Gmail (SMS Backup+). It labels them accordingly and separates them by contact. The downside is that MMS are put on a separate conversation and conversations are limited to 100 messages. But the import process puts them all neatly back onto the phone (except MMS). I don't often have to check for old emails so I don't re-import all the texts when I switch phones, the web interface suffices. It also puts all calls as a calendar event (including length) and entry in the conversations. I find this feature very useful.