Idle games (sometimes called incremental games) are a fascinating genre all of their own, from a psychological perspective, design perspective, and – naturally – a business perspective.

If you’re uninitiated in this world, an idle game is one in which an in-game soft currency constantly increases, even when you’re not playing. Each game has a different currency: Coffee Corp has straight cash, Egg Inc. has its bocks, and so on. You use this soft currency to purchase various upgrades that increase the rate of that soft currency increasing, often exponentially. A big draw of these games is actually the pure satisfaction in how many, how significant, and how crazy these upgrades get.

An Idle Coffee Corp gameplay trailer from TapGameplay on YouTube

It’s a surprisingly imaginative space too and we encourage you to look at some of the big games out there. We’ll link our favourite at the end because there are some important things you should know before you commit…

This article is going to analyse the psychological mechanisms that make idle games have incredible retention rates, the business of gaming impact they have, and what the future of idlers might look like. 

First things first:

Idle games are addictive

That might seem like an over-the-top or sensationalist statement, but the core loop that they’re built on is well established to quickly create a habit out of a behaviour. You might know that cycle better if we describe it as a Skinner box.

B. F. Skinner is probably the most famous behaviourist next to Pavlov, and he created small chambers in which he intended to study behavioural conditioning. That is, how you reinforce a behaviour psychologically. He set up a system where a rat could press a button and be given a reward, usually food. Once that association had been learned, the rats would keep pressing the button even if it only gave food now and then, or at random.

Games that reward players for repetitive actions are called Skinner boxes because they enforce a behaviour that quickly spirals into addiction, or mindless action. Think slot machines in a casino. Idle games have the player clicking a lot and their reward is a number going up, and then that reward becomes purchasing something, and so on. Don’t get us wrong, lots of games do this in tutorials to teach or guide, but idle games are more than Skinner boxes…

They also jump right into the deep parts of our brain with accumulation desire and loss aversion. Back in our hunter gatherer days, accumulating things like food was key to, you know, living and that need to have things is thought to be a holdover from then. Loss aversion is similar, but stronger. Studies like prospect theory suggest that the pain of losing something hurts twice as much as the joy of gaining something. Read more about loss aversion in our blog post on psychological tricks in games here.

Idle games let you constantly accumulate things – which the brain loves – and the pain of loss is almost zero because every loss (purchasing things) only lets you accumulate things faster.

These mechanisms together lead to idle games being some of the most behaviourally addictive around. So much so that the idle games subreddit is one of the few with video game addiction help links in the sidebar.

Does this mean that idle games are evil? Absolutely not, but knowing why we do what we do is important to stop it becoming a problem.

But this does lead us right into a conversation about the players themselves.

Idle games have dedicated players

Idle games have a huge amount of daily active users, as you can see in the graph from GameAnalytics below. 

 Don’t get distracted by those yellow bars. The top 25% of hypercasual games do have a huge upper limit and blow almost every other game genre out of the water, but if we look at the median and bottom bars there we can see that idle games lead over all these other genres. Further, on average idle players are showing about 5.3 sessions per daily active user compared to hypercasual’s 4.6.

And on top of that, idlers are leading the way in terms of session length too!

So idle gamers are playing more often and for longer than in their hypercasual counterparts. So how about retention?

Across all genres, idle games come in fifth at day 28 retention, but are leaders over all others in the arcade genre. This data comes from this great talk from GameAnalytics, and is worth watching for some further info.

In terms of gameplay, this retention could be because of two things:

  1. You get more resources even when you’re not playing, so players are motivated to check in now and then because that boost and welcome message feels good. This is the same desire that motivate people to check Facebook 20 times a day – that need for an update (this is the operant conditioning effect; the Skinner Box).
  2. There is no losing in idle games and prestige systems mean that players can essentially restart the game when it starts to get boring for them. 

So when we’re talking casual games, idlers are marathon runners compared to sprinters like hypercasual. And that makes sense looking at the psychological mechanisms behind the genre as we laid out above.

Idle games are superior to hypercasual in a lot of ways then, so are they actually an insight into the future of hypercasual as a genre? Should hypercasual be learning from them and are they already?

Yes and no.

Are idlers the future of the hypercasual?

In a previous article, we discussed how hypercasual games can respond to their declining growth. One of the ways we spoke about was by shifting into the hybrid casual genre, a term coined by Deconstructor of Fun.

In short, a hybrid-casual game has the mass appeal, simple gameplay, and low fidelity graphics of a hypercasual game, but with surprisingly deep features underneath. It allows them to draw in a lot of users, and then keep those users for much longer than usual as they get pulled deeper and deeper in. With that longer commitment, these games can monetise users with in-app purchase instead of purely advertising, which increases lifetime value of players significantly. Combining the cheap user acquisition of hypercasual and higher lifetime value per player of midcore games means a best of both worlds scenario.

Currently, Archero is the best – and in our minds most typical – example of this genre. Incredibly simple gameplay (touch to move) with roguelite and customisation elements that are much deeper than a casual player would expect.

Idle games fit the criteria to be a hybrid-casual game nicely. Their gameplay is incredibly simple, often no more than tapping over and over and then tapping upgrades now and then. Their graphics are also low fidelity and accessible, and could have been part of the immense success of Cookie Clicker – a game which sprung the genre into popularity in 2013. Idlers also tend to have increasingly deep gameplay on top of the simple initial gameplay that (along with that “one more click” addictive quality) keeps players playing…

Idle game are a genre of their own though, and while they will likely make up part of hypercasuals future, we don’t think they’ll make up all of it.

It’s the present of idlers that we’re interested in right now, and it would be very unlike this blog not to talk about how they monetise.

Monetising Tap Titans

In general, idlers are very well suited to an in-app purchase heavy revenue model. There are tons of opportunities to add them, from reducing cooldown of a boost to buying an in-game currency multiplier. The power of hybrid-casual is that they’re perfect for ad revenue too, just like hypercasuals.

Ads must be implemented well, unlike hypercasual games that don’t necessarily care about a player staying for longer than a day. Read more about those unit economics in our hypercasual article.

Tap Titans maintains this balance perfectly, and it’s their use of rewarded video that’s especially worth noting. 

Screenshot Image

Image from the Tap Titans 2 Google Play Store page.

Rewarded video is a popular ad format because it puts the player in control of when they watch a video ad and then gives them a boost or currency in return. It’s particularly good in idle games like Tap Titans because of the long sessions times and highly engaged playerbase. And, even better still, Tap Titans integrates it visually into their gameplay through a little fairy that players can ignore or happily tap to get that needed boost.

Beyond that it uses in-app purchases for boosts, customisation items and equipment, and an in-game hard currency (paid for with real money) that allows you to revive companions at key moments. 

The game capitalises expertly on the entire life cycle of a player – both the early players discovering how everything works, and the committed metagame players willing to spend money.

With Tap Titans being as well monetised as it is, is this the model for the future of idle games?

Probably not.

The likely future of idlers

Idle games have been slowing down in terms of growth lately, even though the data above makes them seem so promising.

So what’s stopping them breaking into the mainstream fully?

Gameplay.

It’s true that idle games are uniquely addictive, but if the next big success on mobile builds off of the hypercasual genre then idle games need to attract and keep the “accidental gamer”. The people who don’t call themselves gamers, but fill the odd five minutes in their lives with mobile games. 

Unfortunately, idle games rely on commitment. A person filling five minutes is unlikely to become deeply engaged with the tapping gameplay in that short time, and those first five minutes are key. Plus, hypercasual players always want new content which is why studios pump out many games in the genre, but idle games take time to create. The future of idle games would need to optimise these first few minutes and streamline their development, but here’s the thing…

The future of idle games isn’t in idle games.

Instead, we believe that other genres will learn from idle games and take their most addictive mechanics while innovating on the core gameplay loop.

A perfect example of this is in Idle Heroes, which (oddly) isn’t an idle game but does use idle game mechanics. The core gameplay is that of an auto-battler with a huge amount of metasystems on top, but the idle game staple of constant soft currency accumulation is the satisfying backbone. It’s what makes it so addictive, despite its complexity.

Idle Heroes made $100M in a year, and this Deconstructor of Fun article is a nice breakdown of the mechanics that made that happen.

Screenshot Image

Image from the Idle Heroes Google Play Store page.

It’s a complicated game, but imagine the power of an idle game currency system in an uber accessible hypercasual title.

The future of idle games won’t be so idle anymore, but oh how they’ll be profitable.

As promised, our favourite idle game is the browser based Universal Paperclips in which you play an A.I. running a paperclip factory which soon spirals into world combination. We told you idlers are creative. 

Jump in, it's freeeeee 🎉

You’re in good company. Over 500 game devs
worldwide are working with us already!

Get started

Connect

Admix Discord

Come and chat with other game devs or throw your questions at the Admix team.
Join

Facebook Group

Learn from our group of 10,000+ creators and founders as they build brilliant games.
Join

YouTube

Watch the latest videos in our home-grown series What a Game, In-Play Monetisation, and Game Day.
Join

Stay on top of the game! 🎮

The latest game industry trends & updates every Friday in your inbox (no spam).