Do I need a sequencer or more practice with finger drumming?

I recently discovered the Koala app since I'm trying to learn how to sample and make music. I'm slowly getting the hang of the workflow after a few days of messing with it.

My main problem is that I cannot get the drums to sound right. Every time I try to lay down a simple beat, it ends up stuttery and out of rhythm. I know this is due to my lack of skill in finger drumming but I'm wondering how people get their drums to sound so perfect. Do I just need a lot more practice drumming or would a midi controller/sequencer help?