Flycast

Flycast is an open-source emulator, in its README’s words, for the “Sega Dreamcast, Naomi, Naomi 2, and Atomiswave”, derived from the older reicast and developed by Flyinghead. It runs on Android, desktop computers and as a RetroArch core. On Google Play it is free, with no ads, and has more than 100,000 downloads. It is not affiliated with Sega.

What it runs

• Dreamcast games from disc images (CHD, CDI, GDI, CUE), including games built on Windows CE.
• Naomi, Naomi 2 and Atomiswave, Sega’s and Sammy’s arcade boards of the same era, from ROM sets in .zip or .7z files. Version 2.7 added multi-screen support for Airline Pilot, Sega Strike Fighter and Derby Owners Club.
• Graphics through OpenGL ES or Vulkan, with a higher internal resolution than the original and optional widescreen hacks for many games (off by default). On phones with Adreno graphics, custom GPU drivers can be loaded.
• Controls: game controllers, an on-screen gamepad you can move and resize, adapters for real Dreamcast controllers, and rumble. Android TV has its own launcher entry.
• RetroAchievements, off until you sign in, and VMU memory card saves, which Android’s own backup can copy since version 2.7.

The BIOS, and what is built in

Flycast ships no Sega BIOS. For Dreamcast games it falls back to reios, its own replacement written in C++, which, as its source header says, draws on public reverse-engineering notes of the original boot ROM and bits of the redream emulator. The source also writes three small values into the emulated BIOS area to work around bugs in three games: The Grinch, a Jeremy McGrath motocross game and Rent a Hero. The font table the BIOS normally provides is rebuilt from freely licensed X11 fonts. The community wiki recommends a real BIOS where you can, and a few titles, plus MIL-CD discs, won’t start without one (see the questions below).

Two other things are built in. Settings presets for some arcade games, such as free play or a printer switched on, are loaded only when a game has no saved settings yet. And a table of game information taken from MAME, the arcade emulator (the file is marked LGPL-2.1+), includes the game keys that Flycast uses to decrypt many protected Naomi M1 and M2 and Atomiswave cartridges. For Naomi M4 cartridges the table holds only an ID: the decryption data comes from a key file inside the ROM set itself. Either way, they are useful only with ROM sets you supply. Box art and achievement lists come from online services, not from the app.

What goes online

• Crash reports: on by default. When Flycast starts after a crash, it uploads the crash dump and a log to Sentry, a crash-reporting service. The log contains the last log lines, the app version, the renderer, your GPU driver and the ID of the game you were playing; the setting says “No personal information is included.” Turn it off in Settings › Advanced. Our scan lists no trackers because this code is part of Flycast’s own native library, not a separate SDK.
• Box art: on by default. Flycast looks up the games in your library by ID or name on TheGamesDB.net, and arcade artwork on the project’s own GitHub site. Turn it off in Settings › General.
• Online play: Dreamcast games that dial out connect through DCNet (flyca.st), the project’s free service. Naomi network play, GGPO and Battle Cable matchmaking only connect when you use them.
• In our reading of the code, another app on the phone can set the RetroAchievements server address, a feature meant for offline proxy tools; it matters only after you sign in to RetroAchievements.
• There is no update check.

The microphone permission is asked for at runtime, for games that used a microphone peripheral. Android’s backup copies Flycast’s settings and its data folder, which includes a BIOS file if you keep one there.

About this file

• This is the project’s own build of Flycast 2.7, from its GitHub release of 19 August 2026, signed with the developer’s key (Flyinghead). The build file names that key “uploadkey”, so the Google Play version is most likely signed differently by Google; we couldn’t check, so don’t count on updating one with the other. The Play version may also be newer.
• 2.7 added frame-rate detection and pacing, translations including Brazilian Portuguese, better modem emulation and fixes for the online features of several games.
• The 36.3 MB file runs on ARM and x86, 32- and 64-bit, and needs Android 5.0 with OpenGL ES 2.0.
• The screenshots are the project’s own, showing the video settings on a phone and on a TV; the project’s other screenshots are mostly of commercial games.
• Flycast is licensed under the GPL-2.0 or later; some bundled components, such as the xBRZ scaler, are GPL-3.0.

CPU types in this build: arm64-v8a (64-bit ARM, almost every phone since 2017); armeabi-v7a (32-bit ARM, older and budget phones); x86 (32-bit Intel, emulators); x86_64 (64-bit Intel, emulators and Chromebooks).

Recent releases on the project’s GitHub. We host and check only the newest one. Full changelog.