can you record through the 3.5 mm jack? I know that you van record through the mic in the front of it, but it would be nice if you could do it another way.

you can. months ago i bought a splitter adapter that gives me a separate mic input (mono) to the n810. i thought i would use a good little mike to record music rehearsals and shows.
turns out i mostly use the bult-in mic of the nokia headset anyway. the sound quality of the mic seems surprisingly good, at least good enough for the frequency response and sample rate available with seqretary recorder. nothing you would want to release maybe, but john lennon and others worked with far worse hardware than that and got results...
if you get different results with a line in or mic please let us know!

I've used the Voice Recording ap with the built in mike, Nokia headset and a Bluetooth headset. All worked well for my needs.

wesgreen;
I found that the Seqretary recorder is the best available.
I have used it to test for media projects in a pinch and found it to be fine.

the variable gain is really useful.