No iPhone game genre is more competitive than Tower Defense, but that's what start-up ICS Mobile chose when it came to its game Navy Patrol: Coastal Defense.

The decision was made even more interesting by the company's financial situation: as CEO Joe Bayen explains below, it funded development via bank loads and credit cards.

Pocket Gamer: Can you explain a bit about why you formed ICS Mobile?

Joe Bayen: ICS Mobile was set up to build location-based mobile applications with an initial focus towards mobile couponing apps.

We had strong prospects with various major US retailers. However the 2008 financial crisis lead to severe budgetary cuts in IT departments, which pretty much doomed the development of our custom location-based coupon apps.

This setback forced us to use our location-based knowledge for applications we thought could interest iPhone users, which led us into our first attempt at iPhone gaming with the development of iTag Live.

It was a real-time location-based multiplayer first person shooter application - think Lasertag with your iPhone, plus the ability to communicate live with your team via voice, and locate all players on an integrated radar/GPS map - we like to make things simple.

However, iTag Live was a couple of years ahead of its time. The 3G network in the US couldn't handle the amount of data needed for smooth gameplay, which lead us to cancel the project and resulted in our second major setback.

From that point we decided to focus on pure gaming. One reason is some of us have gaming backgrounds from previously working at In-Fusio games, which developed Age of Empire Mobile for Microsoft, but also because gaming is a major revenue generator in the App Store.

What was the inspiration for Navy Patrol: Coastal Defense as the Tower Defense genre is very competitive?

Cash flow was the first inspiration. Following our two major setbacks, we had to scale back our development team from six to three, and we had to rely on bank loans and credit cards to survive. We decided to apply our thinking out-of-the-box mentality to a well known genre to maximise our chances of success.

Back in early 2009 when we started the project, the Tower Defense market wasn't so populated. We thought we would have the game up and running by mid June, however it ended up being a lot more complex than anticipated. Combining a fluid simulation engine, which uses a lot of processing power, on top of an open field TD game, which also uses a lot of processing power, and adding the RTS/RPG elements was a daunting task.

Additionally, we had to simultaneously take on a new iPhone project to make ends meet so we spent six months developing two projects with two programmers and a game artist.

We submitted both projects at the same time, and we had a big sigh of relief when both ended up being featured on the What's Hot section during the same week. From that point on we knew our pain and suffering was close to an end. Needless to say, without the major App Store exposure, this would have been the end of the road for us.

How much comparative analysis did you do on other Tower Defense games and how did this shape Navy Patrol?

We did a lot of comparative analysis because we wanted to mix the best of the Tower Defense breed with our out-of-the box thinking approach. We knew Fieldrunners was the gold standard and that game was successful and unique because it was an open path TD game. We knew we needed to match that since open path TD games are technically a lot more complex to create than fixed path TD games.

We also wanted to differentiate the game by setting it on a water-based environment but we realised we had to up the ante by developing a solid fluid simulation engine to make it stand out.

Additionally, we had to reach to our gamer instinct. We're all gamers and we specially enjoy RPG/RTS-type games, which led us to the development of the RPG-inspired skill tree system, as well as the different specials. We wanted to give gamers the ability to create their own gaming strategies.

Our system is set up so only a limited amount of points can be allocated to each special category during a single game session; hence gamers need to decide whether to allocate their experience points towards technology, offence or defence special categories. The point allocation limitation contributes to make each gaming session unique and adds a lot to the replay value.

Finally, we wanted to create a storyline that would follow the game updates. There are currently 15 chapters scheduled and gamers need to beat at least 50 waves of the easy chapter to unlock a new one. The map delivery layout was inspired by Pocket God and we believed it would make each new game update more exciting for gamers.

What's your AWS Realtime 3D Fluid Simulation Engine all about?

Our fluid engine is a water simulation we designed to fit the game's art style. It's a 3D mesh we integrated into the game that responds to actions (ship explosions, finger touches etc).

All game objects have a simple buoyancy reaction caused by perturbations in the mesh. We took advantage of the iPhone's OpenGL implementation to use some advanced functionality such as rendering to texture to create real-time reflections.

Pricing is a massive issue on the App Store and for TD games, so what are your views on 99c as a price point?

We dropped our price to 99c as a limited weekend offer to introduce the game to a wider audience. Additionally they are tons of tower defense games out there and we felt like dropping the price to 99c would help generate some buzz.

But there's also a long term approach to the 99c price tag. We see it as an investment for future customer acquisition. Our first update will include the newest Facebook Connect SDK, which will allow gamers to brag about their scores directly through their Facebook Live feed, which we hope will contribute to virally expand the buzz around Navy Patrol.

We're planning on raising the price to $1.99 after the current weekend sale and we will have it back to $2.99 once our third map is approved by Apple. Then the $2.99 price tag will be our base price.

We believe that even at $2.99, gamers get a lot of value, since the game will include 15 chapter maps with free specials and turrets upgrades.

What are your thoughts about micro-transactions?

We won't charge for extra content. We're gamers too and we don't think that it's proper to squeeze out every cent. We've decided the success of the game will be determined by positive reviews as well as the word of mouth.

Thanks to Joe for his time.

You can follow ICS Mobile via web.

To get Navy Patrol: Coastal Defense (currently $1.99, €1.59, £1.19) hit this App Store link.