I disagree with all of the above estimates - largely because they haven't taken into account the real cost of maintaining the kind of server infrastructure required to run a free to play game like Clash of Clans effectively. Non-free to play games, or ones with just in app purchases may not incur the same kind of overheads, so can be cheaper.

One quote I've been given is that it can cost $1 per player, per day to run your server infrastructure, tracking your player's habits and building up a database of their behaviour. I'm inclined to believe that it can be done more cheaply, but I don't think this number is unreasonable. If you have ~200k players, your monthly bill is going to start running well into the millions. You'll need the cash at bank to run your game for at least a few months after launch or you'll fail to get out of the gate.

If you're expecting said 200k players, you'll need a cool $16.8 million just to run your infrastructure for the initial three months.

In order to be successful, you'll need to hire people to analyse the data you're gathering, so you'll want a statistician (data analyst) and a player psychologist at the minimum - both of these are expensive people to have. Building and maintaining the software for your infrastructure will require someone with extensive networking, security and database experience, the kind of people you'll be competing against banks and other high paying industries to retain.

You'll of course also need developers and administrative support to handle the actual game development, as others have mentioned above.

Realistically, I would estimate your initial investment prior to shipping your game will probably in the order of $20-25 million.

You mean a new brand new company need 20-25 million initial investment to develop and publish a game? For real? Tons of game company out there and i don't really believe all of these company have such capital to run their game.

You mean a new brand new company need 20-25 million initial investment to develop and publish a game?

I can't speak for ambershee. A triple-A game does cost that much to make. To make a game for the web and two mobile platforms won't cost that much to get to launch. However, the platforms you're talking about demand continued support post-launch. Easily 75% of the effort is spent after launch. These games have to be supported with new content and updates with lots of communication with the user community, if you want the game to continue earning money for your business. And after your first game has become a success, you have to continue supporting it while you start working on a second one (necessitating expansion of the business). So it's probable that my $1-2M was lowballing, but I think it would take quite some time to get up to the tens of millions, working on one game for web and mobile.

Agree with above but with condition this is a popular and good selling game, i believe developer or publisher wont spend much effort on low profitable game. Customer service, event and update are important for online game.

Tom is correct that generally speaking, a mobile game will not cost that much to initially develop - a healthy feature set with a good amount of polish will probably only run to around $1-2 million and can certainly be done for much less if you're clever about it. If you intend to build a game and throw it onto the market as a premium title, or a title that relies on a simple set of IAPs with limited post release support (i.e no content updates or additions, no customer analysis and adjustment), then your budget will probably not run significantly higher than this figure.

The question though, was a game like Clash of Clans - this falls into a slightly different tier, as they have more post release support and continually iterate on the product. The success of a free-to-play game like this relies on the ability to gauge how players are interacting with the game and in particular the monetisation system. This is complicated stuff and can be quite unpredictable - as a result you want three things:

1) An extensive database encompassing and continuously tracking significant player behaviours within your game environment and your monetary environment.

2) Specialist people who can analyse this database and understand why people are doing things and how to adapt the game so you continue to get the most out of it. The relationship between players and an IAP based system is not as easy to understand as you might think!

3) The ability to apply updates and adapt the title as player behaviour adapts.

This is the most expensive part of the project - we'll go back to the figure of $1 per player per day for your infrastructure. This adds up very quickly, and when you first launch, it will be enormously difficult to anticipate just how many players you need to be able to scale to support. If you don't offer enough, your game will have serious issues that prevent people from paying, and this will cost you money (and possibly your game), but if you offer too much, you're wasting money on infrastructure you're not using.

Clash of Clans is a big title, so I assumed anticipating a big audience - 200k players for the first three months of running the project could cost $16.8 million - 3/4 or more the development cost of the game itself.

If you are only expecting 5,000 - 10,000 players (a more realistic figure for an unknown indie developer) you can get away with much less, about $0.5 million to $1 million. If the game suddenly takes off however, you will need to have the money in the bank to expand your back-end infrastructure to cope with the demand, and this will have to happen before you can get the return from those players.

Hope that helps you understand my lines of thinking when addressing the question!