Yes, there is a tool that comes with one of the plates for cooking them upright and just removing the stem end.
I split mine in half lengthwise and have found a grapefruit spoon (slightly serrated on the tip) works great for deseeding and deveining and it is really quick to use. Start at the stem end, cut through the seed pod with the tip of the spoon and then just drag the tip of spoon down to the tapered end. Voila!!
I use a little plastic tool that I got free for watching a knife demo in the supermarket a few years ago - I think it was meant to be an orange core remover - just a small plastic tube about two inches long with a tiny handle on top. Works well - but leaves the seeds in the bottom of longer peppers (but I like the heat, so it's all good)