Though it is usually safe its always best to practice caution when using such apps & websites or when engaging with strangers. It is more popular among males as compared to females in most regions.
Random video calling is popular among teens and youngsters and among those who like to connect with people from various countries.
Random video chatting can be a good option to meet and greet people from other countries, understand different cultures, practice a foreign language, know about a foreign country or just as a casual fun activity.