Tapatalk is really the one you'd want to use. If you're using it quite a bit then for the development work alone, I would pay $5.00. For me, I don't always use it on my iPad and more importantly, I just bought the iPhone app full price and 3 weeks later paid for the new version at the discount. Because I'm a brat, I'll wait to cave but really, it's $5. I probably just wasted that typing this message.