How can I be sure that all contacts will be transferred properly?

When you are going to transfer contacts please make sure that following conditions are fulfilled
 - your Smartphone should have a stable connection with your Wi-Fi network (no walls or other obstacles in between).
 - Make sure that all Gigaset handsets are switched on and are in the range of your Gigaset IP- base station.
 - log off  from Gigaset IP WEB configuration page otherwise the ContactsPush App cannot establish a connection.
 - do not edit contacts in your Smartphone directory while ContactPush App is running. Your edited contacts will not be transferred.