I was a long time user until yesterday. Due to working at MSFT, I had been on the 7/8 windows phone train for a few years with a few devices, latterly a 925.
I'm not a power user, I don't use social media apps, just a few daily texts, a bit of browsing, music and podcasts. I also liked the simplicity of the UI.
Ultimately, I got tired of the crappy inbuilt podcast app and lack of decent alternatives. My wife bought me a second hand apple 5s which arrived yesterday.
I already miss the 'swipey keyboard'.