A GSM iPhone is one that uses the Global System for Mobile Communications technology—the standard for over 80% of the world's mobile connections. When a carrier sells an iPhone under contract, they often lock it to their network, preventing you from using another provider's SIM card. An "iPhone GSM tool" is software designed to remove this restriction, allowing the phone to accept any compatible SIM card worldwide.
"Elias?" Garris called out, hearing the lack of keyboard typing. "You giving up?" free iphone gsm tool v2.6