1. Introduction of the game:
Madden NFL Mobile is an incredibly popular football simulation game developed for mobile platforms. It offers players the chance to experience the excitement and intensity of American football, with realistic gameplay and stunning graphics.

2. All characters and levels of the game:
In Madden NFL Mobile, players can choose from a wide range of real-life NFL teams and players. They can control their favorite stars, make strategic decisions, and compete against other players in thrilling matches. As for levels, the game features various game modes such as Season, Head-to-Head, and Live Events, each offering a unique challenge.

3. What attracts users most to the game:
The game's extensive roster of NFL teams and players is a significant draw for users. It allows football enthusiasts to play with their favorite teams and interact with the players they admire. Additionally, the realistic gameplay mechanics and immersive graphics contribute to the game's appeal, creating an authentic football experience on mobile devices.

4. Why it is popular:
Madden NFL Mobile has gained immense popularity due to several factors. Firstly, its accessibility on mobile platforms makes it a convenient option for gamers on the go. Furthermore, the game continuously updates its content, including new challenges, events, and player updates, ensuring players always have fresh content to engage with. Lastly, the multiplayer aspect of the game, particularly the competitive Head-to-Head mode, fosters a thriving community of players, encouraging friendly competition and social interaction.

5. When the game was released and how many versions are currently available:
Madden NFL Mobile was initially released in August 2014. Since then, multiple versions have been launched, with each iteration improving upon its predecessors in terms of gameplay mechanics, visuals, and features. Currently, players can enjoy the latest version of the game, which incorporates the most up-to-date NFL rosters, gameplay enhancements, and additional content.

6. The most difficult part of the game:
One of the most challenging aspects of Madden NFL Mobile is mastering the intricate strategies and tactics required to outwit opponents. Learning how to effectively manage player stamina, execute precise plays, and make intelligent decisions under pressure can prove to be difficult for newcomers. Additionally, building a competitive team and optimizing player chemistry adds another layer of complexity to the game.

7. Strengths and weaknesses of the game:
Madden NFL Mobile excels in its realistic gameplay, impressive graphics, and extensive roster of NFL teams and players. Its regular content updates, multiplayer features, and engaging game modes keep players invested. However, some players may find the game's reliance on in-app purchases or the initial learning curve challenging.

8. What other games have been developed by the same developer:
The developer behind Madden NFL Mobile, Electronic Arts (EA), is renowned for its array of successful sports games. Some notable titles from EA Sports include FIFA Mobile, NBA Live Mobile, and NHL SuperCard, offering similar immersive experiences across different sports.