FAQ
Frequently asked questions
Does it cost anything, is no sound a fault, what happens while you are away, how to move your progress: common questions in one place.
Answers to questions people are likely to have about Crystal Cavern. For anything not covered here, or something that does not work, please get in touch through the contact page.
Before you play
Does it cost anything?
No. Both the browser version and the iPhone app are free, and there is nothing to buy inside the game.
Where can I play?
In your browser, from the home page of this site. It works on computers and phones. On an iPhone there is also an app on the App Store; it is the same game.
Do I need to sign up or log in?
No. There is nowhere to enter a name or an email address.
Are there adverts?
The browser version shows no adverts in the game (the reading pages on this site may show some). In the iPhone app, a short video advert plays only when you claim a bonus from the Bonus tab. You choose each time, and the game can be finished without watching any. Bonuses are limited to ten a day, and the count resets when the date changes.
While playing
There is no sound. Is something broken?
No. The game was made from the start to use no sound at all: no effects and no music. The reason is in Why I made a game with no sound.
Do crystals build up while the game is closed?
Yes. While you are away they build up at half the usual rate, for up to eight hours. When you come back, "Welcome back" appears and you collect what built up.
What is the daily gift?
A gift that waits for you once a day when you open the game. It runs in a cycle of seven days, and the seventh gift is bigger. How much you get depends on how fast you are mining at the time. Days count the days you opened the game, so missing one never sends you back to the start. It only begins once you have some automatic income. The seven-day calendar and the next gift are always shown in the Bonus tab, and if today’s gift is still waiting you can collect it there too. In the iPhone app you can also double it with a short video, which is always optional.
Do crystals build up while paused?
No. Pause stops both income and tapping completely, and paused time does not count as time away either. Use it when you want the numbers to stop.
I missed a glowing orb.
An orb appears every ten minutes and fades after fifteen seconds. If you miss one, another comes ten minutes later. Each time you open the game, the first one appears after about three minutes. The timer only runs while the game is open and not paused.
Numbers are shown like "1.23 × 10⁴¹".
That is a short form that keeps very large numbers on one line. It is used from one trillion up. "1.23 × 1041" is a 42-digit number: 123 followed by 39 zeros.
Does the game have an ending?
There is no set ending. Even after all twelve seams are open, the depth keeps growing. Stop whenever you like.
The text is too small to read.
Choose from four sizes under "Text size" on the Menu tab, and from five colour schemes. See Text size and colours.
I want to change the language.
The language is set automatically by your device or browser. Seventeen languages are supported; anything else shows in English. In the iPhone app you can also change the language for this app alone under Settings → Apps → Crystal Cavern → Language (on iOS 17 and earlier, Settings → Crystal Cavern → Language; the item appears when more than one language is set on the iPhone).
Your data
Is my progress saved?
Yes, automatically, and only on your own device. Nothing is sent to a server.
Can I continue on another device, or between the browser and the app?
Yes. Under "Save data" on the Menu tab, press "Make a code" to get a string of roughly 50 to 90 characters. Paste it where you want to continue and press "Load". Loading overwrites the progress already there.
My progress has disappeared.
In the browser version, clearing your browsing history or site data also clears your progress, and private browsing does not keep it once closed. Lost progress cannot be recovered on our side either. If it matters to you, make a save code now and then and keep it somewhere safe.
Can I play offline?
The iPhone app works without a connection; it only goes online for adverts. The browser version needs a connection to open the page.
Will I get notifications?
Only in the iPhone app, and only if you allow them under "Reminder settings" on the Menu tab. You get one silent reminder when what builds up while you are away reaches its eight-hour limit. Nothing else is ever sent.
Other
Can I stream the game or post it on social media?
Please do. No permission or notice is needed.
I found a bug.
Please let me know through the contact page. You can also open the report page from "Report a problem or get in touch" on the Menu tab, which has a button to copy your device details; sending those along makes the cause much easier to find.