Maybe we would have more peace of mind without mobile phones? I'm always on my phone, usually tweeting or surfing and I use most of my spare time (while traveling or waiting for someone) on my phone. At the end of the day, I realize I haven't had any 'me-time' or any time by myself. This happens to so many people and they realize that in the long term, they have lost touch with their true selves and one of the contributions is their mobile phones, along with the complimentary TV watching and mindless eating.
But at the same time, I can't count how many times my mobile phone has eased my life. Cellphones have helped us to keep in touch with our friends and family, where as in the past we used to use messengers or letters by post. (It's ironic though, that even with easier technological access to our family and relatives, families are only breaking apart and familial ties are getting more and more strained, but I digress).
At the end of the day, just as Beata Stasak said, the mobile phone is just another tool - it's up to us how we use it....Just like a knife - it can be used for good, e.g. chopping veggies to make a family meal - or it can be used for evil, e.g. murder.
Most people these days, however, like to complain about how technology has complicated life. I'll get back to tweeting now lol :D