I recently upgraded my mobile to the new HTC Desire. This freed up my HTC Magic which my wife is now using. This meant that I needed to migrate all my data from a HTC Magic to the HTC Desire, and migrate all my wife's data from a Nokia N96 to a HTC Magic. This article deals with a few different Android Market place Applications, and the Pro's and Con's of each of them.
Whatever brand your existing mobile is you can usually download their custom software and backup your data ready for migration with this, like the Nokia PC Suite. Alternately using an application like Microsoft Outlook will often allow you so Sync your phone and then dump the results as .csv or XML. From there it is just a matter of finding the right restore method for you.
The Android phones kind of have a live online backup system in place already. Whenever you add a contact, or a send and receive emails through Gmail then all the data is saved in your Google account as well. Because of this I did not need to migrate and contact info, or email data. There are several applications for backup and restoring SMS messages, with subtle differences in each:
This application requires that you sign into your Google account. What it does is actually backup your SMS messages as and when you receive them. It posts them to your Gmail, and labels them as 'SMS messages'. Handy as you don't need to tell it to do this again in the future, it just runs all the time.
SMS Backup and restore allows you to backup your SMS data in an XML format, so that you can restore it wherever you want to. The goo thing with this is that you can edit the format of the export, so that it can be made compatible with other platforms. There is the option to run scheduled backups as well. I used this Application to backup my HTC Magic's SMS messages, and simply copied them over to the HTC Desire's memory card and restored them. It is very quick and easy to use.
This application will allow you to import a variety of differently formatted data packets containing SMS data. One of pre set formats is for the Nokia PC suite. I used Nokia PC suite to dump a data file of the SMS data from the Nokia N96, I copied that onto the HTC Magic's memory card, and this application translated it into a HTC compatible format. You can even set which folder on your phone they will be imported into, if you want to keep them separate for example.
Astro file manager is pretty much 'Windows explorer' for your Android phone. It allows you to browse the installed memory card, and perform actions on the files. You can backup and restore applications to the memory card, so you don't have to re-download them. You can delete, move and attach files to emails. It is a really handy file management application. I used to here mainly to find the SMS backup files, as I forgot where I put them :-).