We always remember the first phone we used with fondness.
I walked into the mobile world with the Samsung M6560 Lindy back in 2010.

At that time there was a wave of the Samsung corby phones! Everyone loved and used them. This one was on the same lines but had music shortcut keys which made it look different. Talking about the performance of the the phone, there wasn't much to write home about but it had amazing looks. The camera was satisfactory for its time. And most importantly it had 3G. Back then it was a big thing and 3G was just starting to catch air.
Then moved on to the Nokia 5230, Samsung Galaxy Ace, Blackberry Bold, Sony Xperia Z and currently on iPhone 6s.
Among all of these, I loved Xperia Z the most because I used to tinker with its OS all the time with Custom Firmwares. Though I did jailbreak the iPhone, but was unable to use payment apps like PhonePe, HDFC bank app due to the jailbreak (Just a heads up if you're planning to jailbreak your iPhone).