As you might have noticed, a new service is now available: Remote Sim Unlock
If none of the available free methods work for you, you can purchase an unlock code for your phone for more than a decent price. The service is based on a 3rd party application (with due costs) and it generates unlock codes based on the IMEI of the phone. Because different carriers code their phones in different way, you have to make sure you’re not using an unsupported network. Also make sure your device is supported.
Please check out the supported devices page. If you really need to unlock another brand, or you’re just locked in an unsupported network, just leave a message and I’ll manually look into it as manual unlocks are possible.