Sprite Stitch Board!

If this feature is in there, I haven't found it. This very important feature is the ability to mark which stitches you've already completed on the pattern. I've tried coloring the completed pixels a different color, but that becomes confusing and difficult to manage. Am I missing something, or does KG Chart really lack this important feature?

As far as I know, that feature doesn't exist. I usually print off my patterns and use a highlighter. That way I can stitch wherever (which is nice when one has a crawling 10 month old. )

Yeah it's not really something that's widely needed, since the makers of these programs expect you to print your patterns off and do as Kareesh does!
Also, I find that I don't need to mark off what I've done - occasionally I will duplicate my pattern and paint the stitches I've done another colour, but that's only to count how many stitches are done and how many to go
But yeah, I find it unnecessary as a tool so it's not something I really miss. That's just me personally though!

I don't have a printer, and it would be a very good feature for a beginner who doesn't have the sixth sense of cross-stitching that blackmageheart does.

PC Stitch doesn't have that feature either. It would be a great one though.

I usually save a working copy of the pattern and erase stitches as I go. Once I'm finished with one colour I fill the area back in and move to the next colour. Works reasonably well.

I don't like printing, so I push mine into PDF format and when I put it on my iPad I can highlight what I've done there. Not so helpful if you have a coloured pattern, but for black and white (which I dont mind) it works great.