A couple of days ago, developer duo Firaxis and 2K Games announced that Sid Meier's Ace Patrol - which is already available to download from the Dutch App Store - will be released globally on May 9th.

Ace Patrol is a free-to-play turn-based air combat game set during World War I. In it, you take to the skies in one of 30 authentic aircrafts, and battle other fighters across 120 action-packed missions.

We recently got a chance to chat with legendary Civilization developer Sid Meier about Ace Patrol, the free-to-play model, and Civilization V on iOS.

This is what he said...

Pocket Gamer: What served as your inspiration for Ace Patrol?

Sid Meier: A couple of things. I guess I've always been interested in historical-type topics and I've never actually done a game about World War I airplanes.

I've done jet planes; submarines and pirates; railroads and civilisations; and things like that. So, it's been a topic that's always been interesting to me, but I've never got around to doing a game about it.

Also, looking at the iPad and the iPhone, and the types of games that would work there, we were kind of leaning towards something turn-based.

That's the kind of environment in which the iPad lives, you know?

You might have two minutes to play, you might have ten minutes to play, you might have an hour. You never know how long you're going to have to play, so something you can interrupt at any moment is good.

It felt like there'd be some interesting strategy there. Some interesting role-play with the pilots and the planes, and just a colourful time period with lots of interesting things going on with the very first airplanes.

Ace Patrol is downloadable for free and contains in-app purchases. What made you choose this business model? Did you consider any other models?

We considered a couple of options. I definitely wanted players to be able to try it for free because we're kind of new in the iOS market and it's fair to give people the chance to play it before they decide whether they're going to buy it or not.

There are all different philosophies, all different types of in-app purchases. We kind of went more with the 'try for a while and if you like it you can buy big chunks of it' model.

It's not like every five or ten minutes there's something you've got to buy.

So, it's more like the model we're kind of used to, i.e. the free demo and then the opportunity to buy the game if you like it.

What do you think of the free-to-play model in general? Do you think it suits every type of game?

Well, it's an interesting model from both a player's and a designer's point of view.

It's different from the buy-it-all model. You know, the triple-A model. And somewhat of an evolution of the model we talked about before (the free demo and purchase model).

I think within free-to-play there's a wide variety of approaches. Again, there's what I call free-to-play with a capital F, which is where there are many things to buy and you're constantly encouraged to do that.

I think it can be done tastefully and it can be done not so tastefully. We're trying to really respect our players. I'm a player as well, and I know what I appreciate and what I don't appreciate in games.

So, I don't think it's universally a bad thing, but it's something that could potentially be abused.

Ace Patrol has been 'soft-launched' on the Dutch App Store. Have you been taking user feedback from that territory and do you plan on implementing new features into the global release based on that feedback?

That's actually been one of the most rewarding and useful parts of our history, I guess, at Firaxis.

You know, there's a very strong fanbase for Civilization. We've had lots of interesting feedback ideas for XCOM and many of the other games we've done.

So, we definitely want to open up a channel of communication with our players, and see what things they like and what things they don't like. What they'd like to see improved, and what they'd like to see more of.

So, we'll have forums available and places where you can go to communicate with us and communicate with other players.

It's definitely a part of our development. We really like to incorporate ideas from our players into our games.

Do you plan to update Ace Patrol in the future? Maybe with more missions or new aircrafts?

It's possible. We're not really in the business of holding stuff back for later. We really want to put all the good stuff in the game from the off.

I think it's important that we make the best game that we can. Hopefully, you'll tell your friends about it and they'll tell their friends about it.

So, holding content back is not really a big part of our strategy. But if we find that - again, in talking to our players and getting feedback - there's one part of the game they'd like more of or something done in a different way, we're receptive to those kinds of suggestions and ideas.

Once Ace Patrol launches to a wider audience on iOS, do you plan to release it on other platforms? On Android and PS Vita, perhaps?

Anything is possible. With this first game, we're in a bit of a learning mode.

We want to learn what things work and what things we need to do better. What's the balance between the iPad and the iPhone? Which versions do people enjoy the most?

Each platform has its own strengths and weaknesses. Are there things we could do in a better way on a different platform that would encourage us to go there, or are there problems with other platforms that would make us think twice about going there?

The core game idea, I think, is something that can certainly work on other platforms. It's really a question of finding out whether our customers are there.

There's a group of people who like the kinds of games we make. Are they playing on PC? Are they playing a lot of mobile? Are they playing a lot of consoles?

You know, where are those people? How can we find them?

It's a constantly changing landscape. Every year, there's a new technology. The Steam Box, for example, is coming out and this and that.

It's hard to say even two or three months from now what the hardware landscape will look like and where it makes sense to go.

So, what are the current limitations you encounter when developing for the likes of iOS? Are controls the main hurdle?

Controls are definitely one of the major things we think about.

It's really critical that the interface, the way the player communicates with the game, and the way the game communicates back to the player are as seamless and as clear as possible.

The touch interface is a lot of fun. It's a very tactile thing. You're directly engaged while giving orders and commands and telling the planes what to do.

There are things we don't have that you do get on PC. Like the mouseover, for example. We don't have that functionality on a tablet or phone.

The ability to rotate. You know, there's cool stuff that you want to take advantage of on the tablet and phone platforms. The gyros, the cool gestures, pinching, and rotating, and that type of stuff.

You look to see what each platform does well, and try to integrate some of those cool features into the game. That's part of the fun of working on a new platform and imagining what the possibilities are.

We recently spoke to Firaxis about the forthcoming iOS port of XCOM. Project lead Jake Solomon told us that if the response to the port is positive, a port of Civilization 5 wouldn't be completely out of the question. Is this something you'd personally like to see?

Again, it's one of those decisions that involves the hardware and the audience, and where we are in terms of resources and things like that.

We certainly believe that turn-based games work well on iOS and tablet-type platforms. Ace Patrol is turn-based, XCOM is turn-based, Civ is certainly turn-based. So, we think the format works well.

Civ can take a long time to play. Is that the kind of game you want on your tablet? I think it probably is.

You know, a lot of people take tablets on airplanes and flights and things like that, where they're looking for something to keep them busy for a couple of hours.

Can we do the graphics justice on that platform? That would be another question. There's a big difference between the tablet and the phone. For example, in terms of the size of the screen. Would something that works on the tablet necessarily work on the phone?

Those are the kinds of questions we need to ask ourselves before we make that kind of decision, but - in some ways - I think it's a good candidate.

Would you consider porting some of your studio's back catalogue to iOS, then?

I love our back catalogue.

I would certainly like to see some of those games come alive again, but it really boils down to the same set of considerations: will they work on the platforms? What's the market? What are our players looking for?

Another thing we're really hoping to get out of this first game and then communicating with players is ideas. "I liked Ace Patrol, but I'd really like to see this game that you have in your portfolio on iOS" or whatever.

Whenever I go to a trade show or a convention, people say "when's the next Pirates or the next Alpha Centauri or the next Gettysburg!" or whatever their favourite game is.

That's really how we get a sense of what people are looking for. A big part of why we did XCOM was because so many people were asking for that game and wanting it to be remade.

We'll see what the reaction is and what we hear from our players in terms of the kind of things they'd like to see in the future.

Back to Ace Patrol, then... How will you determine if it's a success or not? Revenue? Number of downloads?

I think our primary measurement there is really the feedback we get from our players. You know, are they having fun? Are they encouraging their friends to play?

We get a lot of that through the forums and different avenues right now. We're a business, so we need to be paid. We're hoping that financially it goes okay.

Our games traditionally have had a fairly long life cycle, whereas on mobile platforms, for example, games tend to have a short life cycle.

So, that would be another measurement for us. If we can extend the life cycle of the game towards the life cycle we traditionally expect.

If it stays active for a long time, that would be another indication that we've made a game that's resonating with people and bringing them back to play over and over again.

That would be another measure of success for us.

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