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I have a DZ09 Smartwatch and i found the Funrun app works completely. I have connection, SMS and phone push, and full integration with remote picture and video. I'm using a Nexus 5 with its highest Android version, I think 6.1 or so.
http://imgur.com/ES6jPWL (Perspective, it's not that bad)
People may bash these things, but for 10 bucks, I'm happy with it. I use mine as a backup cellphone, gym trainer since it has Bluetooth I keep my music on it and leave the cellphone at home, and as well... a watch. I keep a sim card in it that lasts for a year, so I always have emergency calling on hand.
https://play.google.com/store/apps/details?id=com.szkct.funrun.main