Your battery would run out by the time you finish typing an e-mail!
I have purchased haptic pro as well and its definitely a fantastic app. This was one thing I actually really liked about some of the android based phones since the haptic feedback gives a sense of actually pushing a button, now I can have it on my iPhone 4. I feel like I can actually type a lot easier now with as funny as it may seem.
I purchased this haptic pro 5 days ago and have been using since. I dont noticed any lagness and dont notice any battery drainage out of the norm. I charged my phone 3 hours ago and I still have 51 percent on battery life. The best part is that I can adjust the vibration.
I played around with it. It was hit/miss as to when it actually worked, so I uninstalled it. It seemed like it worked most of the time, but then it would just stop working for 5 or 10 seconds.
Just bought it. Very cool. I wish there was a sbsettings/activator to turn it off/on.
It's surprising how effective the feeling is. The trick is to adjust the slider to a small vibration, as a big one get's irritating - fast.
I'm using Haptic Pro. I was pleasantly surprised to see that it remembered my original purchase from my iPhone 3G days, as the app didn't work on the 3GS for ages, so I had completely forgot about it.Is haptic working on 4.1?? I havent tried yet but it feels very weird typing without vibration again.