f61 Browser Demo: No App Installation Required

This site’s original demo runs in the browser. No app installer or APK is supplied here, and no official app for the queried name is verified. You do not need an account to start a virtual round. This guide provides no unknown download link, sideloading instruction, credential-recovery procedure or security-bypass step. The local wallet rules still apply on a phone browser.

Choose a virtual stake of 10, 20, 50, 100 or 200; the initial selection is 20. Starting a round immediately deducts and saves the captured stake. Stake, mine setting and refill are locked during play. Covered eligible cells and the sound control remain available. The bank button becomes available after at least one safe reveal. There is no automatic queue of rounds and no selectable mine count other than four.

The board has four rows, four columns and exactly four mines. Number columns from zero on the left. Columns 0 and 2 must have the same parity of mine count and different counts; columns 1 and 3 must have the same parity, but their counts may be equal. Matching parity allows two odd counts as well as two even counts. There are 370 legal boards. One is sampled uniformly when a round starts and remains fixed throughout that round.

You can bank manually after the first safe reveal. Revealing all twelve safe cells or having no eligible reveal remaining banks the current quote automatically. Proven mines and previously revealed cells are unavailable. An individual move whose prospective quote would exceed 1,000× stake is disabled. With this particular 370-board support, however, the maximum reachable quote is 355.2× stake, so the 1,000× guard is never reached.

The initial virtual balance is 1,000. At settlement, the game adds any previously saved fractional carry to the gross quote, pays the integer part into the wallet and saves the remaining fraction separately. Carry is a payout remainder, not a fee or fractional wallet balance. While idle with a balance below 10, manual refill sets the integer wallet to exactly 1,000 and preserves carry. Refill is not available during an active round.

The integer wallet, including zero, and the separate fractional payout remainder persist in this browser’s localStorage. The stake deduction is saved when a round starts. Reloading an unfinished round does not resume it or refund that stake: the reduced balance remains saved. There is no account recovery, cross-device synchronisation or saved active-round state. A settled balance can persist across ordinary reloads.