Short answer: pick Anvil-MC if you want a free, always-on server you control (with mods, plugins and Bedrock support) and have an Android phone to spare. Pick Aternos if you want free hosting with no hardware and don't mind the server sleeping when nobody's online. Pick Realms if you'll pay monthly for a vanilla, zero-maintenance world.
These are the three most common ways to host a Minecraft server without running your own PC. They solve the same problem very differently. Here's the full comparison.
At a glance
Anvil-MC — host on your own phone
Anvil-MC turns an Android device into a Minecraft server. Because the server runs on hardware you own, it starts instantly, never sleeps, and gives you full control — file browser, RCON console, and a web dashboard. It offers two engines: PumpkinMC, a fast Rust-based core for lightweight sessions, and Custom JAR for Paper, Spigot, Fabric and Vanilla with full mod and plugin support. Every server gets a public subdomain automatically, so there's no port forwarding.
- Strengths: free, always-on, mods + plugins, Bedrock cross-play, full control, no networking setup.
- Weaknesses: you provide the phone; keep it charged; player count scales with device power.
- Best for: friend groups who want a persistent modded or plugin server for free.
Aternos — free cloud, but it sleeps
Aternos is the best-known free host. You need no hardware at all — everything runs in Aternos's cloud, and it supports Forge/Fabric mods plus Bukkit/Spigot/Paper plugins. The trade-off is availability: servers stop when the last player leaves, and starting one puts you in a queue because free capacity is shared. For a scheduled hangout that's fine; for a world your friends can drop into anytime, it's frustrating.
- Strengths: genuinely free, zero hardware, mods and plugins supported.
- Weaknesses: idle sleep, start queues, shared/variable performance, less direct control.
- Best for: occasional sessions where someone manually starts the server first.
Minecraft Realms — official and effortless, but vanilla
Realms is Mojang's own subscription service. It's the most hands-off option — always online, no setup, no management — and it's the safest bet for non-technical players. But it's paid every month, player slots are fixed, and it does not support server-side mods or plugins. You get vanilla Minecraft (plus datapacks) and nothing more.
- Strengths: always-on, official, effortless, cross-play on Bedrock Realms.
- Weaknesses: monthly cost, no mods/plugins, limited slots, minimal control.
- Best for: vanilla groups who want zero maintenance and will pay for it.
The core trade-off: Realms buys you convenience with money and gives up mods. Aternos gives you mods for free but gives up uptime. Anvil-MC keeps mods and uptime for free — in exchange, you supply a phone to run it on.
Which one is right for you?
- Have a spare Android phone and want a free, always-on modded server: Anvil-MC.
- Want free hosting with no hardware and only play occasionally: Aternos.
- Want a vanilla world with zero setup and will pay monthly: Realms.
Coming from Aternos? The most common reason people switch is the idle sleep and start queue. Running Anvil-MC on an old phone left on the charger removes both — the server is simply always there, and you keep your mods and plugins.
Note on Realms + mods. If your group's whole reason for a server is a modpack or plugins (economy, minigames, custom biomes), Realms can't do it at all. Only Anvil-MC and Aternos support server-side mods among these three.
All three get your friends into a shared world without a PC. If you want the fullest control and the best uptime for free, and you have a phone to dedicate to it, Anvil-MC is the pick — download it from the Play Store and you'll have a server running in about a minute.