I am still on Windows Phone since 2012. Started with WP7.5 (Lumia 710) then WP8 (Lumia 520) in 2013 then WP8.1 (Lumia 1520) in 2014 which I am still using until now. I upgraded to WM10 but recently I reverted my Lumia 1520 back to WP8.1 and replaced the battery and I am getting 4+ days on a full charge, so I am still happy with the system and have all the apps I need and can do everything I wanted from my phone. No plans to consider Android or iphone. I am waiting for the Surface Phone to see if it will be a worthy upgrade.