In terms of performance, you can expect the device to hold up pretty well as there is a 2GHz octa-core chipset along with 1GB of RAM.
To help you store images, songs, apps, and other data, the Samsung Z4 makes its mark with 8GB of internal storage space that can be further expanded using a microSD card up to 128GB.
Battery and Connectivity
The Samsung Z4 comes bundled with multiple connectivity options that include 4G, Bluetooth 4.1, dual-SIM support, GPS, Wi-Fi 802.11 b/g/n, and a microUSB 2.0 port.
Fuelled by a Li-Ion 2,050mAh battery, it is expected to support talk time up to 7 hours.
Method to recover contacts from samsung z4
You can recover Contacts from Samsung z4 with this Samsung Data Recovery software,it ont only allows you restore deleted or lost contacts on Samsung z4, but also can help you restore pictures, videos and contacts from Samsung smart phones directly.
More info:Recover data from broken samsung z4