Welcome to Android Central! From what I can tell, that's a budget phone, with a Unisoc T760 CPU (Unisoc is not known for high-end processors) and only 4 GB RAM. It's not going to compare well with a current or recent iPhone, but it's also not fair to compare them, since (a) it's a completely different platform, and (b) the ZTE is around $140 USD, and the iPhone is around $580.