iPhone SE
iPhone 5
Bush E4X Spira
ZTE Blade
ZTE Kis
Nokia Lumia 635
also:
Nexus 7 tablet
iPad Air
All used for dev apart from the Nokia windows phone, that was my intention but B4W never happened (no bad decision since Windows for phone didnt either).
I am currently using a Samsung Galaxy S8 (my main-device) and on my desk I also have a Nexus4 and a Samsung Galaxy S3. I managed to get hold of these for free with some client-projects I did . I also have an ASUS tablet.
Then, I have an iPhone6 for iOS-development (and for a long time it was my main-device).
That said, the best device I have ever had is my HTC HD2!
First it ran Windows Mobile (and my Basic4ppc apps) and then I modified it to use Android (with help of all friends at XDA). Even today, Android 7.0 is available for it along with other SO such as Windows Phone, Unix and other SO-ports. This is/was a very versatile phone and the size is just perfect although today my eye-sight is not the best and the screen is a bit too small for reading. The graphics and UI:s made for this phone are really amazing. I miss using it a lot but it is still on my desk...