1. Introduction of the game:
PUBG Mobile is an immensely popular mobile battle royale game that has taken the gaming world by storm. Developed by PUBG Corporation, it offers thrilling multiplayer gameplay where players battle against each other on a sprawling island map.

2. All characters and levels of the game:
In PUBG Mobile, players have the option to choose from a wide range of characters, each with their unique appearance and abilities. The game features various levels and maps, including Erangel, Miramar, Sanhok, and Vikendi, all providing distinct terrains, challenges, and strategies.

3. What attracts users most to the game:
Users are captivated by the immersive and intense gameplay experience that PUBG Mobile provides. The game's seamless graphics, realistic mechanics, and thrilling combat scenarios keep players engaged, making them want to come back for more. Additionally, the constant updates and introduction of new features enhance the overall gameplay experience.

4. Why it is popular:
PUBG Mobile has gained immense popularity due to its highly addictive gameplay and its ability to create adrenaline-pumping moments. The open-world environment, extensive weapon arsenal, and the element of surprise make every match a unique and exhilarating experience. The game's immense popularity has also led to the rise of competitive esports tournaments, further cementing its position as a fan-favorite.

5. When the game was released and how many versions are currently available:
PUBG Mobile was initially released on March 19, 2018. Since then, it has witnessed numerous updates and improvements, with currently two main versions available: PUBG Mobile and PUBG Mobile Lite, the latter being a lighter version suitable for low-end mobile devices.

6. The most difficult part of the game:
One of the most challenging aspects of PUBG Mobile is the high level of competition and the need for strategic thinking and quick reflexes. Surviving till the end requires mastering various skills such as looting, shooting, and understanding the map dynamics to outmaneuver opponents. This constant need for adaptation and decision-making adds to the game's difficulty.

7. Strengths and weaknesses of the game:
PUBG Mobile's strengths lie in its realistic graphics, immersive sound effects, and vast open-world maps, creating an unparalleled gaming experience. Additionally, its constant updates and optimizations ensure a seamless gameplay experience. However, one weakness is that occasional bugs and technical issues may hamper the gameplay for some users, requiring regular patches and updates.

8. What other games have been developed by the same developer:
Apart from PUBG Mobile, PUBG Corporation, a subsidiary of Krafton Game Union, has developed various other games in the PUBG universe. These include the original PLAYERUNKNOWN'S BATTLEGROUNDS (PUBG) for PC and consoles, as well as spin-off titles like PUBG: New State and PUBG: Battlegrounds Mobile India. These games offer diverse experiences within the sandbox battle royale genre while staying true to PUBG's core gameplay mechanics.