I'm trying to sync text messages between Android and Windows 10 Mobile, or at least have a solution to move them from Android to W10M and preserve all formatting. (My main device is Android, but I like to use my idol 4S or Lumia once in a while.)
I've used both the "Contacts + Message Backup" and "Transfer My Data" apps to backup and transfer SMS messages on my W10 devices. Unfortunately, they don't work very well and have issues when trying to get the format the same as Android messages. For example, group SMS (which are actually in MMS format) are often restored on W10M as single messages; additionally, the meta data appears in the message body, which is very distracting.
So, I'm researching to see if it would be feasible to make my own apps. For W10M, I want to know where in the file system does the OS stores SMS messages. I can see the full file structure on my Lumia 1020 and idol 4S (former is interop unlocked), but I can't seem to find where the actual messages are.
This may be impossible, in which case I may have to deal with formatting the messages once they are exported via the Contacts + Message Backup app.