Exponential Idle is an Idle Game for smartphones released in 2020. In it, you play as a talented undergraduate student who gets asked by his professor to converge a formula which is an exponential recursive equation into a finite value. Not knowing how to solve it, you make a small program that calculates it for you. As you progress, you start upgrading and using more variables to make numbers grow faster and progress with your research. The game also has some of the largest numbers seen in idle games, with them having the ee notation later on (for example, ee54.129 means 10^(10^(54.129)).
This game provides examples of:
- 15 Puzzle: You can play the 15-puzzle minigame to earn stars, with its size depending on difficulty (3x3 on easy, 4x4 on medium, and 5x5 on hard).
- A.I.-Generated Economy: You can buy autobuyers for variables and upgrades, with each one pressing the Buy All button at the max setting every second,though it can be sped up. Due to the speed, this may make purchasing upgrades difficult if you have a variable autobuyer and vice versa, though there should be no problems if you have both and you can always turn them off.
- Cap: The game defines infinity as its cap. At first, it's ee200$, or 10^10^200$. However, doing a Supremacy lets you increase the infinite value. It becomes close to impossible to progress after getting ee2400$, though.
- Cash Gate: To progress the story, a certain amount of money or db must be reached. For instance, to get to the "Some Hope" chapter, you have to get more than 1.0000=e20 db.
- Cool Teacher: The professor, who is supportive of your project and gives you the Prestige currency that can be spent on permanent upgrades.
- Deliberately Monochrome: The game has absolutely zero colors other than grey and white (or black and white if you're playing with Dark Theme on), as a game heavily centered on math wouldn't really need color.
- Dump Stat: The lowest variables, which fall in usefulness as the game progress. Don't be surprised when the boost from x gives 0% profit when compared to other variables, as even if it's free trying to boost something that mostly relies on y and higher variables (like x=64y+2^3*100, when y=15z+2^6*128 which is clearly much higher and there are variables above that) isn't going to work well. The game even gives you the "Why Are You Doing This?" achievement for upgrading it 1000 times.
- Experienced Protagonist: Your character starts off as a talented undergraduate student with professors who see a promising future ahead of him.
- Export Save: Unusual for a mobile game, but you can export the approx. 20KB save into the clipboard and paste it into the game or a document.
- Leaning on the Fourth Wall: The player character mentions after the second Prestige that this is beginning to feel like an idle game.
- Loads and Loads of Loading: Not initially, but after getting Auto-Prestige and doing it and Supremacy a lot, your super high profits and frequency of Prestige-ing turns so high that it can take several minutes for the phone to calculate how much money you've earned while the game was off and ultimately finish loading.
- New Game+: Doing a Prestige makes you lose all upgrades but gives you a Prestige currency for new upgrades, labeled as μ. An upgrade lets you perform it automatically after a certain time or a certain ratio of db to b is reached, even when the game is off. A long time after that you can eventually do a Supremacy, which makes you restart the game at b=0.001, but gives back all the stars you spent during the game. It also allocates a Supremacy currency for more new upgrades named ψ, making it a New Game+^2.
- Not-Actually-Cosmetic Award: Every achievement earned gives you stars which can be spent at a shop.
- Number of the Beast: You get the Devil's Advocate achievement for gaining ee666 dollars.
- Player Nudge: Tapping the acceleration button ten times in a row makes the game give you the "Hold, Not Tap" achievement, making it clear that it should be held to be used properly.
- Rare Random Drop: There's a 0.04% chance that tapping the equation will give you a star. Every second also has a 0.04% chance for getting a star.
- Shout-Out: Some achievement names are references.
- Your Princess Is in Another Castle!: The chapter called "The End" (that comes after your graduation and Master degree) is not the last one, there are at least four more after it where you earn further honors.