App not working correct on IOS 10.0.2

Hello,

I need a little bit help.
My Ionic is running on Android and my iPad (IOS 9.3.5) without problems. But on my iPhone (IOS 10.0.2) it is very slow und not correct running. The Push Notification does not register, the HTTP-Request does not working (I see only the template without data).

But when I resume (press Home-Button and then start the app again) the app, everything is working???
The clients told me, the app is running without problems and from ony day to next the app have this problems.

Have you some ideas? I update Ionic, Cordova, create a new project and update all plugins.

Your system information:

Cordova CLI: 6.4.0
Gulp version: CLI version 3.9.1
Gulp local:
Ionic CLI Version: 2.1.4
Ionic App Lib Version: 2.1.2
OS:
Node Version: v6.9.1

Plugins:
cordova-plugin-admobpro 2.20.1 "AdMob Plugin Pro"
cordova-plugin-calendar 4.5.5 "Calendar"
cordova-plugin-compat 1.0.0 "Compat"
cordova-plugin-console 1.0.4 "Console"
cordova-plugin-contacts 2.2.0 "Contacts"
cordova-plugin-device 1.1.3 "Device"
cordova-plugin-extension 1.5.1 "Cordova Plugin Extension"
cordova-plugin-google-analytics 1.6.0 "Google Universal Analytics Plugin"
cordova-plugin-network-information 1.3.0 "Network Information"
cordova-plugin-splashscreen 4.0.0 "Splashscreen"
cordova-plugin-statusbar 2.2.0 "StatusBar"
cordova-plugin-whitelist 1.3.0 "Whitelist"
ionic-plugin-keyboard 2.2.1 "Keyboard"
phonegap-plugin-push 1.8.3 “PushPlugin”

Thanks for your support
BR Thomas