Apollo Emulators
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Apollo Boy multiplayer

Connect two handheld games nearby, through an online room, or by exchanging direct invite links.

Help pages

Apollo Boy uses an emulated link cable for two players, with Game Boy, Game Boy Color, and Game Boy Advance games. Each device runs both players’ games, and each player controls their own handheld. Connecting a second controller to one device does not create a second linked handheld.

See the shared Multiplayer guide for general network help. The requirements below apply to Apollo Boy’s handheld link play.

Bring the right games

Both players need Apollo Boy and the game files; the app never transfers a game file to a friend. For the same game, both need the exact same version. For different compatible games of a series, both devices need both exact game files in their libraries. Open your own game on each device before connecting. Different revisions or hacks count as different files too, so do not assume matching titles are enough.

The games must support linking with one another. GBA games link to GBA games; GB and GBC games use the Game Boy link hardware, and compatibility between those cartridges depends on the games. A GB/GBC game cannot link to a GBA game. Only two players are supported. Use matching app versions; direct invite links explicitly refuse a different app version.

Nearby: same Wi-Fi, free

  1. Put both devices on the same Wi-Fi and open the games you want to link.
  2. On one device, open the game menu and choose Link cable…. Under NEARBY, choose Host (wait for a player).
  3. On the other, open Link cable… and choose Join [the host’s name].
  4. Keep both apps open while they connect, then use the game’s own link or multiplayer option, as you would with a physical cable.

You can keep playing while waiting for a player. Stop hosting stops the nearby advertisement. If no host appears, check that the Wi-Fi allows devices to reach one another; guest networks often isolate them. Android and desktop builds can link when their versions and games are compatible.

In Link cable…, ONLINE is a section heading, not another menu to open. Making a room needs purchased Pro in the Android app from Google Play; a trial does not include hosting. Your friend joins free without an account or sign-in. Desktop builds can join rooms but cannot host them, and cannot use a relay.

  1. The host chooses Host a room… and sends the displayed six-character code or room link to their friend using Share code and link… or Copy code.
  2. The friend chooses Join with a code…, enters the code in Code, then chooses Join. With an empty code, Paste accepts the friend’s message. On the room’s details page, choose Join again to ask the host. A shared room link can open the app into the room instead.
  3. The host checks who is asking and chooses Allow or Decline.
  4. Once linked, use the game’s own cable feature.

If you leave the room page while waiting, Online room… takes you back. A room link is different from the direct invite exchange below: it needs no reply link. A closed room needs a fresh invitation. If the app says an update is needed, update before trying to join again.

Rooms try a direct connection first. A relay can help Android players on some networks, when available; it is best effort, with no purchased relay hours. If online play is busy and no direct path works, the app waits and retries for up to 10 minutes. Cancel stops that wait. A working direct connection can continue while the relay is busy. After three hours relayed, Still playing? asks whether you are still there.

These are already available alongside rooms. Starting one needs purchased Pro; opening a friend’s link is free. A trial cannot start one. They connect directly without the room service or a relay, so some networks cannot connect this way.

  1. The host chooses Link cable… > Play by invite link….
  2. Choose Share link or Copy link and send the complete link to the friend.
  3. The friend opens it, or chooses Open an invite link…, pastes it in Link, and chooses Open. Their app shows Your reply link.
  4. The friend sends that reply using Share link or Copy link.
  5. The host opens the reply, or uses Open their link… to paste it. Both apps must remain open while they connect.

The initial exchange waits up to 10 minutes. A reply belongs to that invitation; if it is expired or belongs to another invitation, make a new one. Send links privately to the person you intend to play with. On desktop, starting an invite still needs purchased Pro; desktop room hosting remains unavailable.

While linked

Both games run at 1x with standard audio. Fast-forward, rewind, cheats, reset, and loading save states are unavailable while connected. Saving a state remains available, but it captures your game, not a resumable two-player cable session. Opening the menu does not pause the linked games. Keep both apps in front; leaving an app shows a waiting message to the other player. Nearby links and rooms can end after 30 seconds away; direct invites use their three-minute connection window.

Trades and turn-based games are generally less sensitive to delay than fast real-time games. Only link with people you trust: games can exchange names, teams, trades, or other data just as through a physical cable, and a direct connection reveals your network address to the other player. Connecting also sends your whole save and game state for that game to the other device, which keeps them in memory for the session. After setup, play exchanges button presses rather than game files. See Privacy.

Disconnecting and coming back

Choose Link cable… > Unplug the cable to end deliberately. Each player’s own game continues from the linked moment and keeps its own in-game save. The temporary copy of the other player’s game is discarded; hosting does not give you the other player’s save file. Save in your game to retain its progress.

Nearby links and rooms try to recover a dropped connection automatically. A room normally allows 30 seconds for reconnection; when a player left the app and their connection closed, it can hold their place for 60 seconds. Reopening after the app closes can offer Rejoin [the other player’s name]’s game?: choose Yes promptly while the other player keeps their app open and waits. Nearby rejoin has a two-minute window; online rejoin is bounded by the shorter room hold. No declines the rejoin and ends the other player’s wait.

When rejoining, both games resume from the states and saves kept by the player who stayed connected, including the returning player’s game. An older save on the returning device does not replace that session’s progress. If the waiting player also closes the app, or the window ends, start a new session.

A direct invite has different recovery: a dropped connection makes the host create a new link, and the friend must open it and send a new reply. Complete that exchange within three minutes while the games wait. Direct invites do not offer the saved rejoin prompt after closing the app; start a fresh invite.