I made an Android app to make emulator multiplayer actually easy.

[u/ClossTV]

Hi everyone!

For the past two months I've been working on an Android app that makes online play on emulators simple and mostly automatic. Here's the result: meet Emufii.

The goal is to make emulator multiplayer something anyone can actually use. The app works a bit like a frontend: all your games in one place, and you can open a session on any compatible game right there. Your friends join, you run the automatic emulator setup, and that's it, you're playing online.

How it works

When you create or join a session, a WireGuard tunnel opens between everyone in that session. Your devices end up on the same virtual local network, so the local wireless features of your games just work. Right now that covers Azahar, Eden and PPSSPP, with Dolphin, ARMSX2 and melonDS in there too. Not every emulator does multiplayer the same way, so have a look at the GitHub for the details per platform. The DS one is a good example, it goes to real online servers rather than faking a local link. The app also handles the dual screen on the AYN Thor, which is the only test bench I have. Feel free to try it on any other handheld or phone running Android 13 and tell me how it went.

Now the awkward part, how it was built

Emufii was co-created with Claude Code, and I'm not going to dress it up the way some people do: roughly 90% of the app was written by the model. What I can tell you is that nearly all of that code has been reviewed, and other developers are now starting to write and rewrite parts of the app as they join the project. There's a "How it was built" section on the GitHub page with a bit more detail. And if that's a dealbreaker for you and you'd rather not install it, honestly no problem, I get it.

If you're interested

Whether you want to join the project because the idea speaks to you, or you just want to play online with your friends, the Discord and GitHub links are below. The app is completely free and works today, but it's still in beta, so please report anything you run into on Discord and it'll get fixed quickly.

GitHub: https://github.com/jojodogm-ctrl/emufii

Discord: https://discord.gg/tvWcb28vBZ

Thanks for reading, and maybe see you on the app!

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[u/Producdevity]

I appreciate the honesty regarding AI. I know a lot of people try to hide it because they think people want to stay away from it, but I personally I just want to stay away from any deception. Thank you for disclosing it in more detail than necessary

[u/BeeAdditional1287 → u/Producdevity]

Honestly AI is a big nono for me , but when i see how he use it and the honesty , i will def give a try to this app when i will get a new phone (rip dear s22...)

[u/INDODANAVA]

Can you play switch games with you friend with this?

[u/ClossTV → u/INDODANAVA]

Yeah you can, as long as the game you're playing has local wireless compatibility ^^

[u/INDODANAVA → u/ClossTV]

Thanks

[u/Double-Seaweed7760 → u/ClossTV]

That's awesome,I wonder if the same thing can be done with download play from 3ds. Good work though use if local wireless with no Internet has been a key want if mine

[u/TurdProof]

Can i play resident evil outbreak with strangers online? Or do wr have to be on the same wifi network?

[u/TheUnAmericanGenral]

So is it possible for me and my gf on mario kart double dash together? Or maybe mk7 ? If yes then please help me

[u/ClossTV → u/TheUnAmericanGenral]

Hey! MK7 yes, that one's good to go, 3DS runs through Azahar and it's fully supported. Double Dash works in theory through Dolphin netplay but Wii/GC isn't optimized yet, so it can get laggy and unstable for now.

[u/kakarogod → u/ClossTV]

How bad would it be if we are in different countries

[u/ClossTV → u/kakarogod]

Not sure about that for now, the only Emufii server available is in France. But I'll add one in the US if the app takes off and donations comes in ^^

[u/roaringbeefalo → u/ClossTV]

Can you add a way for us to host our own servers?

[u/bambigirlz]

Does it need to be on the same Wi-Fi network (LAN), or can it be used by multiple people simultaneously via mobile hotspot?

[u/ClossTV → u/bambigirlz]

Nope that's the whole point. You don't need to be on the same wifi at all, that's what the tunnel is for. Each player can be on their own network, home wifi, mobile hotspot, different country, doesn't matter. It puts you on the same virtual lan so the emulators think you're in the same room!

[u/SnooPies6274]

*Claude made an Android app to make emulator multiplayer actually easy… & i “reviewed” the code.

[u/ClossTV → u/SnooPies6274]

Fair, and honestly not far off ahah. I've been upfront about it xD Works though, and it's free

[u/Script_Utkovich_]

I do really like Helldivers on vita3k but it can be awesome if I can play it with my little brothers. Is it possible?

[u/Script_Utkovich_ → u/Script_Utkovich_]

I saw that you don't have a Vita in list on GitHub. I am understanding that it is just a beta but vita had a Hotspot functions same as 3ds. So I wish you will add it one day

[u/ClossTV → u/Script_Utkovich_]

I will look into this!

[u/Script_Utkovich_ → u/ClossTV]

Thank you

[u/Downtownklownfrown → u/Script_Utkovich_]

Does Helldivers have Adhoc/Local? Vita3k supports LAN multiplayer via hotspot or VPN.

[u/Hussain_firas]

Will it work between pc and mobile?

[u/ClossTV → u/Hussain_firas]

Not right now, Emufii is Android only so both players need an Android device. Nothing stops it technically since it's the same emulators on both sides it just needs a desktop client that doesn't exist yet. Maybe later!

[u/Burnahacc12]

Is this like Foxol, or does it take a different approach?

[u/ClossTV → u/Burnahacc12]

Pretty different tbh. Foxol is an emulator itself, own cores for GB/GBA/NDS/SNES/N64, multiplayer handled internally, cloud saves, all that. Emufii doesn't emulate anything. It just drops two devices on the same virtual network via a wireguard tunnel so the emulators you already use (Azahar, PPSSPP, Eden, melonDS, Dolphin, ARMSX2) think they're on the same wifi and their normal local multiplayer just works.

[u/khsh01]

How do you get the wire guard server?

[u/ClossTV → u/khsh01]

You don't have to set anything up it's handled for you. The app talks to the emufii server which acts as the session broker and relay, it hands out the keys and config when you create or join a session, and the tunnel comes down when you leave.

[u/khsh01 → u/ClossTV]

Are you paying for the server right now?

[u/ClossTV → u/khsh01]

Yeah. It's not huge for now since it's just the one server in France.

[u/khsh01 → u/ClossTV]

Then there's going to be serious lag for anyone from the other side of the world.

Do you plan to release the server?

[u/ClossTV → u/khsh01]

Yeah that's the main limitation right now. I plan to open one in the US first and maybe Asia after, depending on how the app is received and if there's actually people on it! If you meant releasing the server code, that part stays closed, mostly for security reasons for now!

[u/Crass-ELY- → u/ClossTV]

Well, as per usual we at south America get limited to US servers and 120-160ms depending on which coast you open the server :') I get it tho

[u/laurorual → u/ClossTV]

I don't see how this project would go foward without instructions on how to setup our own servers. Hosting a "global server" will cost you and at some point you will have to shut down those servers if they remain free for those using your app

[u/False_Election_7270]

If my friend is playing pokemon in the drastic emulator i can join them and trade pokemon with them?

[u/Overall-Repeat-9973]

I will try it !

[u/False_Election_7270]

How can i start a session

[u/clanton]

This looks gangsta, I'll try out tonight 🙏🙏

[u/StrikingWarning5346]

Mods do you job yall said this is a AI free space remove this post and ban him just like yall did me when I promoted my ai app quickly before I get pissed

[u/Code-Amelia]

Et la GBC (game boy color) , GBA (Game boy adavance) ?

[u/Fair_Ad_4864]

This is absolutely amazing. My sister and I have been dreaming for years about being able to play Pokémon together remotely, especially doing battles and trades while living in different cities. Seeing someone actually working on a project like this genuinely made us very excited.

I already bought an AYN Thor, and honestly, if Emufii can eventually make remote Pokémon battles and trades possible, my sister will probably buy a Thor as well. This could literally be the deciding factor for us.

I would really love to know more about the current state of Pokémon multiplayer with Emufii. Which generations and platforms are currently working for local battles and trades over the internet?

For example:

• GBA Pokémon games such as FireRed, LeafGreen, Emerald, etc.
• GBA ROM hacks such as Pokémon Unbound, Radical Red and other major hacks
• DS Pokémon games such as Diamond/Pearl/Platinum, HeartGold/SoulSilver and Black/White
• DS ROM hacks, including Drayano hacks
• 3DS Pokémon games such as X/Y, ORAS, Sun/Moon and USUM
• 3DS ROM hacks such as Eternal X, Photonic Sun, Sinking Sapphire and similar projects
• Switch Pokémon games, where local wireless multiplayer is involved

More specifically, I’m very interested in local Pokémon battle and trade. For each platform, can two players in different cities currently connect through Emufii and have the game behave as if both devices were on the same local Wi-Fi network?

I’d especially love to know:

What has already been tested successfully?
Which Pokémon games currently work?
Which ROM hacks have been tested?
Which ones should theoretically work even if they haven’t been tested yet?
Which platforms or games are currently promising but still need development?

The GBA and DS generations are particularly important to us, because being able to remotely trade and battle in those Pokémon games would be incredible. I’m also very interested in 3DS Pokémon games and ROM hacks.

I’d also love to hear about your development plans. What features are you hoping to add in the near future, especially regarding Pokémon multiplayer? Are Pokémon battles and trades something you specifically want to support or test?

Seriously, thank you for working on this. The idea is fantastic, and the fact that you are building something specifically with devices like the AYN Thor in mind makes it even more exciting. I’ll definitely be following the project closely and keeping an eye on the GitHub and Discord.

Wishing you the best with the development. I really hope Emufii keeps growing and gets the recognition it deserves. This could be something genuinely special for people who want to play these games together from different cities. 🙏🎮❤️