MoonCedar Technologiesan app label of AP Competition d.o.o. · Mavčiče

Apps that keep every answer on the device.

MoonCedar builds small Android apps with nothing behind them: no account, no server, no adverts, nothing to buy. The first is Cavelume, a deduction puzzle set in a cave you clear with reasoning alone.

THE STUDIO

A puzzle that can be reasoned out should never ask you to guess for money

Deduction games have a well-worn trick: tune the boards so that a coin-flip turns up often, then sell the way out of it. A safe-tile reveal for a coin, a revive for an advert, a hint bundle when a run of bad luck ends three caves in a row. The genre's whole appeal — that the board is solvable if you think hard enough — quietly becomes the thing being taxed.

Cavelume takes the opposite line. The detector is free and always there, zen mode exists precisely so a slip does not cost you the cave, and nothing in the app can be bought at any price. Where a genuine fifty-fifty does appear, it is named as one rather than dressed up as your mistake.

Everything ships inside the download, so the caves generate and solve on the phone, with no connection and no server anywhere in the loop.

THE APP
CAVELUME

a quiet cave deduction · tiha jamska dedukcija

Uncover tiles to reveal the numbers that count the hazards touching them, then reason out which neighbours are safe and which are not — flagging what you suspect and opening only what you can prove. Clear the cave without setting anything off.

Around that familiar spark it builds something larger: different board shapes including hex-tile caverns, a classic clear, a race against the clock and a relaxed zen mode where a slip does not end everything, plus a detector that lights up a safe tile when you are genuinely stuck. Cave sizes and hazard densities climb as you go, and your best clears are kept to chase.

square & hex caverns classic clear against the clock zen free detector

What logic can actually prove here

One frozen cave, six hazards, nineteen tiles already open. Tap any covered tile and this bench will tell you whether the visible numbers prove it — or whether nothing on the board can decide it. Nothing opens, nothing explodes, nothing is scored.

Tap a covered tileThe bench works only from what the open numbers say — exactly the information you would have in the app.
provably safe
provably hazard
undecidable

One position, frozen, with the answers computed for you — the opposite of playing. Cavelume hands you the cave and nothing else: your own flags, your own detector, hex caverns, three modes and a record that only moves when your reasoning does.

SlovenščinaEnglishchosen on first launch, changed any time
on google play as Cavelume · application id com.deepdig.cavelume
runs android · offline · no account · contains no adverts · no purchases · no data collection
Privacy policy
THE COMPANY

Who publishes it

MoonCedar Technologies is the app name used by AP Competition d.o.o., a company registered in Slovenia. The code, the artwork, both language versions, this website and the Google Play account are handled from one address in Mavčiče.

Registered companyAP Competition d.o.o.
DirectorMarjan Novak
Registered addressMeja 4, 4211 Mavčiče, Slovenia

A cave that looks unsolvable, a detector that fires oddly, or a question about privacy — mail reaches the person who wrote the app. Pišete lahko tudi v slovenščini.

cedar@apcompetition.live

MoonCedar Technologies is a trading name of AP Competition d.o.o., registered in Slovenia at Meja 4, 4211 Mavčiče. Cavelume, its caves and its artwork belong to the company. The Cavelume privacy policy applies to the Android application com.deepdig.cavelume. Copyright 2026.