I used to visit these forums a few times in the past. I have always tried to make games and recently I started to make games for mobile platforms. My latest game is called Concussion Boxing but that is not I came here to ask you about.
I found that making 32x32 pixel art characters is easy enough and fast enough for me so I decided to make an action RPG game based on these sprites for mobile.
Now, I would like to ask you how would you design a mobile game? I have read a book about design but deciding on game scope and content is a big question because the more content you decide to put into your game the more it takes to make it.
Lets ask a dummy question... how many monsters/bosses/NPCs would you want to have in a mobile action RPG game that sells for 1.99$? What would be more than enough? What would be too little?
I hope it's ok I ask you about game design over here and I know it's a subject everyone have a lot to say about. So I hope it's ok with you.
Not counting ports, Battleheart is my favorite mobile RPG. It's not an ARPG per-say, more of a real-time tactical RPG, but it is perfect for touch screen systems. Gameplay changes only a little from start to finish, but each new ability gives you a vast more options on how to play. Difficulty curved appropriately, and the need for grinding was very very low.
The kind of ARPGs I avoid on mobile are the dual thumb stick controls with rings of buttons around them, like the Dungeon Hunter or Zenonia games. I feel twitch gameplay is very shaky with virtual controls, and this sort of game is out of place on a touch screen. Controls should be tight and to the point, and take advantage of the flexibility of a touch screen rather than try and adapt traditional console control schemas. Puzzle RPGs like Puzzle Quest and 10000000 are a good fit on mobile for this reason.
I value gameplay over a long experience. A 2-3 hour game with fantastic gameplay would have me talking about it over a 20+ hour experience involving lots of grinding. Keep it short and sweet, and you'll have users wanting to know when a sequel is coming out.