4G LTE is significantly faster than the HSPA+ technology that WIND is currently employing for mobile internet service. Depending on the method of implementation, real-world LTE speeds can vary wildly, but generally users tend to see upwards of 30Mbps (about 5x faster or more than your average HSPA+ speeds).
More importantly, this means larger capacity for the WIND network. Less chance of dropping out, and fewer lag spikes during peak hours.
The network that Nokia is building for WIND is also going to be constructed with voice over LTE (VoLTE) and voice over WiFi (VoWi-Fi) in mind.
VoLTE is a high-definition voice call that uses LTE towers instead of 3G or 4G. Call quality is better, and there’s some pretty impressive background noise cancellation to boot. Generally, VoLTE customers can only make a VoLTE call to another person on the same network, but the network itself automatically makes the decision whether to connect you as VoLTE, or make it a regular call. All you have to do is dial like normal.
VoWi-Fi is the same as VoLTE, but it uses your active WiFi connection instead of 2G, 3G or LTE. Call quality can be enhanced, but for best results both people need to be on a WiFi network and have VoWi-Fi support.