Iran doesn't really have an air force. Contrary to Tehran's ever-growing missile arsenal, and the nuclear capability it is working to develop in spite of the entire world, Iran's air capabilities are rather atrophied. In fact, Iran's real investment in the air force actually came to a halt 35 years ago, with the fall of the shah and the rise of the ayatollahs.
During the shah's rule, the Iranians received very advanced (for that time) F-14 fighter jets and less advanced F-5 fighters. But after the Islamic Revolution and the Iran-Iraq War, there was an immediate tear with the U.S., resulting in an arms embargo on Iran that only became tougher and wider as the Iranians continued to advance their nuclear program. Iran was left with only a handful of usable aircraft.
Due to international sanctions, Iran cannot even purchase systems from Russia or China. It is true that Iran has manufactured its own planes, based on the F-5, but they were built on outdated technologies and would not survive in modern warfare. However, if, as they claim, the Iranians have succeeded in domestically manufacturing a stealth fighter, this would mean very advanced technology. So far, only the U.S. has succeeded in manufacturing an operational stealth fighter — the F-22 — at an astronomical cost. The F-35, which Israel is supposed to get in three years' time, is still in the experimental stage. Russia and China also have stealth programs, but they are also still in the development and experimentation stage.
So, in my humble opinion, the Iranian announcement of its new stealth jet Qaher ("Conqueror") F-313 should be taken with a grain of salt. First, even the official Iranian announcement admits that this is merely a prototype. There is often a decade or more between the production of a prototype and mass manufacture.
This prototype may very well be nothing more than a simple model, made of wood and plastic, without any operational systems, without any insides, and possibly even without an engine. The jet's diminutive size suggests that it has very limited arming capabilities (a stealth plane carries its weapons inside the aircraft, not on the wings). The cockpit technology looks as if it comes from the 1980s. The inlet cones (which slow the flow of air from supersonic flight speed to a subsonic speed before it enters the engine), as many analysts have noticed, are extremely small, which limits the airflow to the engine and indicates less than impressive capabilities.
In short: The Iranian charade appears to be geared more toward public relations and propaganda efforts than toward the development of an actual aircraft. In any case, the burden of proof is on them.