Nokia writes that N900 can use a hot-swappable 16GB microSD
card and they name as accessory a "Nokia microSD-Speicherkarte MU-44 (16 GByte)" on their German webpage which is a "Nokia MU-44 MicroSD/HC 16 GB"

Is 16GB the upper limit?
Did anybody try more?


Can I use this as memory to store applications, MP3s, photos, videos?

Is there even some kind of backup software which saves the complete system onto such a MicroSD/HC card as this was possible with "BackupBuddyVFS" on the Palm Tungsten T and SD card?

I have a Nokia 32GB Class 2 MicroSDHC flashcard in my phone.
It works nice, havent notice any difference compair to 16 GB.

No, 32GB cards work fine. It's just that 16GB was the largest available at the time they wrote the specs. Storing applications can be a bit tricky, as you can't directly control the install location, but you can certainly store any data files on the card.

There's the BackupMenu application (in extras-devel I think) which allows you to backup/restore a full image. You need to reboot to run it each time though, and it's not currently compatible with multiboot.