How to make an idle game: Everything you need to know about incremental mobile games

Idle games present gamers with an opportunity to play games with long-term targets, test their problem-solving skills and gain incremental rewards over time. This sub-category of games which are known as incremental games or clicker games can have impressive retention rates and session length when compared to other types of games. A GameAnalytics study revealed that idle game players have a stickiness of 18%, compared to 10.5% for other hyper-casual titles. They also show a higher number of sessions per day and a higher average session length (8 minutes). This article shares the essential insights you need when learning how to make an idle game.

What is an idle game?

Idle games are often categorized as casual games due to their ease of use and accessibility. However, they differ greatly from popular hyper-casual games such as Voodoo’s 5 Hoops and Ketchapp’s Origame. Idle games require users to perform basic actions — such as repeatedly clicking, hence the term clicker games — to generate in-game currency and manage automated actions. When playing an idle game, users can progress in various ways without having to actively play — which is where the term idle game comes from — meaning gamers can progress even while sleeping.

Instead of having to perform each task, users can set up processes that will continue while the user is inactive. Idle games can be used to create a satisfying user experience because players are rewarded for returning to your app and maintaining their in-game goals. For example, AdVenture Capitalist is a money-making simulator where users can start out as the owner of a humble lemonade stand. By hiring managers, attracting investors, and by managing their funds, players can grow their empire and become a capitalist tycoon. The player’s ability to push forward with their goals while asleep is a selling point for the game that is noted in the app description and official trailer.

Idle games can also attract users looking for a game that won’t take too much of their time or attention while still offering a substantial gaming experience. The challenge is to use simple actions to use in-game currency in the best possible way, allowing users to incrementally unlock new features and abilities to thrive within the game’s environment.

Why are idle games popular?

Idle games can be a smart business venture for app developers and a great alternative to hyper-casual games for users. Here are four reasons idle games are popular:

• Ease of use: Idle games are easy to understand and have gaming elements that are addictive and fun from the very first session. These games often begin with a simple objective before introducing ways to manage in-game currency, unlockable elements and upgrades.
• Idle games incentivize users to return: By their nature, these games give users a reason to return after every session. Users will have gained in-game currency just by returning to the app, giving them something to look forward to for their next session.
• Long-term goals for users and developers: Unlike other addictive mobile games, idle games have natural pauses in gameplay where the users must wait for their strategy to take effect. This makes it easier for users to have more sustainable usage habits when playing idle games, retaining them for longer.
• Idle games are cost-effective: This type of mobile game is relatively quick to develop and can be extremely profitable. However, idle clickers still need to be marketed to the right audience and have engaging gameplay that can compete with the very best idle games.

How to make an incremental game: Development and mechanics

Development options

There are many different ways to develop an idle game. Unity and Unreal Engine are the two most popular gaming engines available, both of which are reliable options already used by many developers. You will also need to consider whether you need a backend/server, because Idle games are usually light enough that they can be stored on a user’s device. If you do need a backend, this can be written with software such as Python, Ruby or Elixir.

4 idle game mechanics to consider

• Clicker: Tap as fast as you can to generate in-game currency. While this is used in many idle games, it lacks long-term appeal and should be used in conjunction with other mechanics.
• Simulation: Idle games can have a less hands-on approach for users by simulating tasks. For example, instead of using the clicker mechanic, players focus on managing and strategizing.
• Arcade: This is traditional arcade-style gameplay that enables the user to achieve an objective relevant to their targets.
• Merge: Users are able to succeed by dragging and dropping items. This can work particularly well for themes that involve building progression.

7 best practices you need to know when creating an idle clicker

1. Choose a monetization model that won’t harm retention rates

Retaining users for as long as possible is fundamental to monetizing this type of mobile game. The quality of your user experience will determine how long users are retained so developers must prioritize UX over monetization methods that – while successful – may prevent users from returning to your app.

Many idle games are Free-to-Play, meaning that users can install your app for free and expect monetization methods to appear in-app. This could be rewarded video ads (more on this below) and including options to make in-game purchases. To learn more about how to lower churn and boost retention, watch our webinar with CleverTap, “Uncovering the user lifecycle.”

2. Utilize rewarded video ads for best results

One of the best ad formats for idle games is to use rewarded video. This is a video ad that can be watched by users in exchange for a reward. For example, watching a 30-second video could reward a player with in-game currency or other resources that will help them optimize performance. This is particularly well-suited for idle games in which users are always looking for the best possible way to progress towards their goals.

This ad format is less likely to irritate users in comparison to banner ads, interstitial ads and traditional video ads. This is because rewarded video ads are opt-in, meaning that users are only exposed to them if they want the reward. By avoiding disrupting the user experience and incorporating your ads as a way to succeed at your game, you can retain users for longer and boost LTV.

In a podcast with IronSource, Nate Barker, Director of Business Development at Kolibri Games explains that ”Rewarded video works tremendously well in idle games as it provides a way to manipulate speed and payout - two core variables in most idle games. Rewarded video is non-interruptive, and is entirely opt-in, so players like the fact that they can engage with the ad unit at their own leisure.” He also states that these ads can be advantageous for the user: “oftentimes the content that is being advertised is similar to other idle games that the players like. It seems that players are playing four or five [different idle games] at the same time, so we haven't seen any drop in our retention from showing other games.”

In addition to offering in-game currency, another reward you may want to offer users is the ability to speed up time. Given that users must usually wait for time to pass before achieving certain goals, this is a smart way to incentivize users to watch rewarded video ads. You can also offer payout multipliers and special upgrades.

3. Test ad placement and frequency

Your soft launch also presents an opportunity to test two critical components of your app’s monetization. The placement and frequency of your ads will also affect the user experience. It’s important to find appropriate pauses in gameplay to expose users to ads and to monitor the optimal frequency. To learn more about the pros and cons of different monetization methods and ad formats for mobile games, read our guide.

4. Create a unique and attractive theme

Just like all hyper-casual games, Idle games need an appealing theme that will attract new users and create a positive user experience. For example, Cookies Inc. is an idle game where players must build a successful cookie company. While Cookies Inc. has similar gameplay to most idle games, the game has a strong theme that makes it more attractive than the app’s competitors. Users can upgrade their bakeries with special upgrades, collect rare cookies and summon “Cookie Gods” to help with production.

When choosing your theme, ensure that this is something your audience can easily understand and connect with. Other examples of idle games with strong themes include Miner Tycoon, Bitcoin Billionaire and Realm Grinder. These games all have obvious goals that can be immediately understood just by their title.

5. Don’t rely on one gameplay system

Idle games are meant to be about management and strategy. Unlike many hyper-casual games, it's essential that you develop more than one way users can push towards their targets. The most popular idle games utilize several different systems the user can use to succeed, all of which should work together for a unique experience. While it’s challenging to get the right balance between systems, this is critical to your app’s success and should be focused on and tested.

6. Soft launch your game before going global

Before sharing your game with the world, it’s important to soft launch your idle game. By releasing your app in strategically selected territories first, you can ensure your game has been fully optimized for best results. This enables you to set expectations for how your app will perform in the App Store and whether you have created an effective idle clicker that users enjoy. This is a smart way to test your app and avoid problems with your app for your worldwide audience.

7. Respond to user feedback

While this is necessary for all games developers, this is essential when marketing an idle game because you rely on high retention rates for monetization. By listening to user feedback and continually updating your game for a better experience is the best way to maintain a loyal fanbase. You can also make it easier for users to share feedback with you by inviting them to message your social media accounts.

For more valuable insights into mobile marketing, read our guides for how to make a hyper-casual game successful and everything you need to know about mobile video ads for gaming apps. You can also learn more about industry benchmarks with Adjust’s Hyper Casual Gaming Report 2020.