[citation][nom]A Bad Day[/nom]I'm still trying to understand how CoD is such a successful brand despite some negativity. Not sure if studying how it's successful would help me publish an interesting mobile app game (will be ported to desktop first, then to the mobile devices).[/citation]
Call of Duty is successful because of the following factors:
1. It's accessible - a key ingredient to making a game successful is to make it n00b/idiot-friendly. This is the biggest reason Call of Duty is so successful, it caters to people who previously weren't gamers or who are gamers that don't want to play a challenging game (AKA casuals).
2. It's mass marketed - Spend 9/10 (exaggeration, probably) of your game development budget on hyping up the game through marketing and advertising with advertisements that will give the player a sense of how much of a bad*** they are when they will be playing the game. This strategy is effective when you have built up a legion of sheepish customers who will buy your next big game no matter what.
3. Its developers are lazy - Use the source code of an ancient, irrelevant engine, tweak it a little, copy and paste anywhere from 10-75% the assets from the previous game you made with that engine, tweak them, and release the (un)finished package (parts of the game will be made available later, but for purchase as DLC). This strategy saves time and money that would otherwise be allocated into developing new game assets.