It is almost 10 years development of perovskite photo-electronic devices since first report in 2009 for solar cell applications. From then on, fast development for efficiency and stability have been reported, and also various applications, including LEDs, detectors, transistors. Especially, the efficiency is high enough now, and the stability issue has also been improved a lot. So is there any information for the commercialization of perovskite? Is it really a hot field, and what's the future direction for research?