What's the difference?
I don't really use my computer more than emails, social media, Internet surfing, pictures, videos and the odd document.
I don't really use my computer for much more than emails, social media, Internet surfing, pictures, videos and the odd document.
I don't really use my computer much more than emails, social media, Internet surfing, pictures, videos and the odd document.

Those sentences are correct?

Thanks a lot.

Question

What's the difference?
I don't really use my computer more than emails, social media, Internet surfing, pictures, videos and the odd document.
I don't really use my computer for much more than emails, social media, Internet surfing, pictures, videos and the odd document.
I don't really use my computer much more than emails, social media, Internet surfing, pictures, videos and the odd document.

Those sentences are correct?

Thanks a lot.

Answer

The second one is correct. You need the 'for'.   I've heard 'the odd ____'  used as it is in this sentence, implying that it is somewhat rare.  If you often read/create documents on your computer, you would just say 'documents'.

Answer

The second sentence is the best. You need the "for" in order for it to be correct. I would also change "odd document" to "occasional document." We don't really use the word "odd" besides something like "That's odd. He should be here by now."