One of the biggest benefits to implementing a system of dual-currency in a game is the ability to encourage users to spend money by offering virtual goods that can only be purchased in the game with the premium, or paid, currency.

One of the drawbacks to this system, however, is that as developers focus on how to make that high-level tier of virtual goods and its correlative currency as desirable to the users as possible, the basic, or free, currency often gets ignored or forgotten.

The most common way in which basic currency becomes worthless is irrelevance: When all the virtual goods that hold value to a user are only purchasable using premium currency, the basic currency becomes irrelevant to the user. In Habbo.com, for example, pixels (the basic currency) can only be spent on a disappointing fraction of the virtual goods available in the game, and even of those, most pixel purchases required a co-payment of coins (the premium currency). Pixels alone are subsequently worth next to nothing in Habbo– an unfortunate consequence of putting premium currency on a pedestal.

For a developer who wants to maximize numbers of paying users, it seems logical. Why should a game be designed to allow the basic currency to retain value when users get it for free? The premium currency, which (in the absence of a subscription model) is the sole provider of profit for the developer, should be favored and exalted, because the more worth it holds in the game, the more users will want and pay for it.

The error in this logic, however, is the failure to remember the age-old adage: Time is money. Users may not be spending money in order to get basic currency, but in most games, they pay for it with time: time spent completing challenges or tasks, time spent signing into the game and visiting other players– time spent, in other words, simply playing the game.

In DogWorld, users can earn basic currency just by logging in.

Basic currency is a reward for user activity, and when that currency can be exchanged for virtual goods that have purpose, users will continue to desire that currency and, likewise, will continue to be active. And any successful social game or community developer can assure you that retention of a loyal, active and interested player is worth far more than a one-time $19.99 purchase of premium currency.

In other words, as a developer, you shouldn’t overlook what your basic currency can do for your game just because it isn’t a direct transaction into real profit. In the long run, its indirect ability to retain and engage your users will benefit your game as a whole– including revenue– so long as you allow it to stay valuable in comparison to your premium currency.

One easy suggestion? Don’t limit the virtual goods payable by basic currency to the lower tiers. Just as exclusive goods can encourage users to spend money in pursuit of the status symbol, so can they encourage gameplay for that same reason. Providing valuable virtual goods that must be obtained with basic currency means users cannot simply buy their way through the game, but instead must put in the hours.

Remember: successful free-to-play games don’t require a user to spend money in order to enjoy it, either on a short-term or long-term basis; spending money should only enhance an already-solid user experience.

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