Strictly speaking, manga refers to a Japanese comic book. Often in black and white, the comic strip is read from right to left (this is the original meaning). The word "manga" is, by extension, used to designate other products of Japanese culture reminiscent of the manga graphics of the famous comic strip. This is how we find the manga style in many anime and video games (PC, consoles and of course, mobile manga games).
Manga video games are often adapted from anime, which themselves are adaptations of comic books. But this is not always the case and the reverse is also possible. The good thing about this manga theme is that you can find several styles of mobile games. For example, among the games adapted from manga, there are multiplayer, RPGs and strategy games. One game that is very popular with many players is Summoners War. On the other hand, you can also find games with a slightly different graphic style, as is the case with Arknights.
If you can't find what you're looking for among the manga-style video games, find all the categories of mobile games and find your new hobby!