Version history

Protocol 4 version history

Every released version of Protocol 4, newest first. Dates marked with a month only are approximate.

Version 3.0

The biggest update so far: Standoff duels, a mining empire that earns while you are away, syndicates and raids.

NEW DUEL MODE: STANDOFF

The live duel used to be a race — one code, both of you deducing it. Now you can play a standoff instead: each of you sets the code the other has to break, so there are two secrets, and you watch their readings land on yours while you work on theirs. Turns alternate, and a solve only ends the match once both sides have had the same number of turns — so going first is never the thing that wins it. Solve on the same turn and it is level, a result no duel could produce before.

BUILD YOUR EMPIRE

Assemble rigs, expand the vault, run overclocks. Your network keeps mining while you sleep.

SYNDICATES AND RAIDS

Join a syndicate, claim territory, raid rival operators. A share of every raid now feeds the syndicate pot instead of conjuring credits out of nothing.

CAREER

18 contracts, daily missions, and a rebuilt rank ladder where competitive play finally counts.

ALSO IN 3.0

  • Reinstalling no longer wipes your progress: credits, rank, badges and empire all come back
  • Finishing a duel and wanting another takes you straight back to the open-duel board
  • Rejoining a duel gives you back the code you were defending
  • A drawn duel now shows both solves instead of crediting only one
  • Defence tools are charged properly instead of quietly paying for themselves
  • A real iPad layout instead of a stretched phone
  • Six languages across every screen
  • Block, report, and codename filtering
  • Reduce Motion and Dynamic Type honoured throughout
  • Push notifications for raid alerts and duel invitations

Version 2.0

Guess4 became Protocol 4: a new name, a hacker world and real-time PvP duels.

Protocol 4 has been fully re-engineered!

NEW TITLE: Guess4 is now Protocol 4! Welcome to the new era.

REAL-TIME PvP DUELS: Challenge your friends to high-stakes 1v1 hacker battles.

GLOBAL LEADERBOARD: Climb the ranks and become the ultimate Server King.

GAME ACHIEVEMENTS: Unlock exclusive badges and titles as you progress.

APP OPTIMIZATION: Massive performance improvements and bug fixes.

NEW LOCALIZATIONS: Full support for Spanish, French, German, and Portuguese (Brazil).

Version 1.1

Compatibility update: Protocol 4 now runs on iOS 17 and later.

Version 1.0

First release: crack a four-digit code by logic, with daily challenges and a global leaderboard.

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