Although not my 1st Android phone, I had an iPhone 5S before this. I was lucky enough to win this M8 a couple of weeks ago, and have since switched to this over my 5S as my daily. Pros:*Screen size is perfect. Not too big, not too small.*Wonderful battery life. I felt like I was constantly searching for a power outlet with my 5S. I don't have any scientific evidence, but I'd say the M8's battery lasts about 25% longer - at least. *Stellar design. The phone is beautiful and well crafted, even more so than the iPhone in my opinion.*Notification lights.... I missed this when I got my iPhone. Most android phones have LED notification indicators, and that's a huge win. I missed texts and calls all the time on my iPhone.*Incredibly smooth performance, maybe the best I've experienced on an Android phone. My girlfriend has the S5, and I notice sluggishness on it. Not here. *Fun, useful camera effects*Boomsound. I love it. I've never ever played music through a portable device until now. It's quality matches that of a small, premium audio dock - AND in stereo. *Wake gestures. I love swiping the black screen to enter the phone.*SD card slot - I have a lot of lossless music, and love being able to take that with me.Cons:*Screen isn't great... Although res and DPI are high, color seems dull, and doesn't seem super bright - Both of these things are extra noticeable when held up to an iPhone or S5. *Although I like the dual camera features and interface, the camera resolution is poor. Photos always look better from an iPhone or S5.*Heavy. It's significantly heavier than my old 5S and my girlfriend's S5. The weight can be fatiguing.*Phone App/Contacts - For the most part the UI is ok, but I still haven't wrapped my head around the phone app. Everything is cramped and difficult to utilize, especially while moving.*Call quality. Not only is the person on the other line quiet, but sounds a bit robotic. too bad... A phone can't do phone very well.Although it's not perfect, I do prefer it over the iPhone. You can't go wrong with either, but my 2 big concerns were battery life and expandability (for my music collection.) this scores higher than the iPhone for each.