I've tried many jar openers and most are so-so. I just got the EZ Off Jar Opener (Amazon) and it's great. Opens jars and bottles easily. You just need to screw it under a cabinet, wooden table or such (I guess you can just stick it on too). They also have a website if you don't Amazon. http://www.jaropener.com/ I see the website has a 2 for 1 deal.
I have several types of jar openers. 1. Round plastic opener 2. clamp around opener 3. Battery operated opener - my last resort