On August 22nd Iran announced that it had developed, tested and was putting into production a new ballistic missile. This one, called Fateh-313, used solid fuel and had a range of 500 kilometers. This is the latest claimed Iranian development of the Fateh 110 which is a copy of the Chinese DF-11 ballistic missile, which appeared in the 1980s with a range of 300 kilometers and an 800 kg warhead. In the 1990s an improved version, the DF-11A appeared with a range of 800 kilometers and a half ton warhead. A decade later the DF-11 was using GPS (American or Chinese) guidance in addition to the less accurate INS. For nuclear warheads either guidance system is accurate enough. For conventional warheads GPS is essential to avoid missing the target with the smaller explosive power of the conventional warhead. The big change here is solid fuel, which enables a missile to be made ready in less than 30 minutes compared to several hour for liquid fueled missiles like the SCUD.
The Fateh 110 is an 8.86 meter (27.5 foot), 3.5 ton rocket with a half-ton warhead. The first version appeared after in 2002 and had a range of 200 kilometers. By 2010 there had been to improved models, with ranges of 250 and 300 kilometers plus improvements in reliability and accuracy. The Fateh 110 is a solid fuel missile developed to replace the liquid fueled SCUD ballistic missiles Iran had been using since the 1980s. SCUD was developed from the German World War II era V-2. In 2008 Iran licensed Syria build the Fateh-110 as the M600. In 2010 some of these were apparently transferred to Hezbollah. Apparently the only Fateh-110 type missiles to be fired in combat were two Syrian M600s fired at rebel targets in 2012.
In 2011 Iran claimed to have created an anti-ship missile, called the Khalij Fars, with a range of 300 kilometers based on the Fateh 110. What all this implies is that Iran is claiming to have developed a ballistic missile that can hit moving ships at sea. China is also claimed to have developed this technology (the DF-21D). But neither country has demonstrated their anti-ship ballistic missiles actually working.
In fact there is little evidence, in the public record that any versions of the Fateh 110 are effective or exist in large numbers. Iran regularly announces wondrous new weapons, developed entirely in Iran. Very few of these weapons are ever seen in service. Still, the Iranians can handle modern tech and it is possible that their Fateh 110 missiles, or at least most of them, would work in wartime.