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Mar 2026 – Aug 2026 · 5-month build

Building PalmPilot for Project Zomboid

The five-month journey behind PalmPilot, a functional handheld organizer mod with persistent device data, multiplayer Beam transfers, useful apps, and authentic late-1990s details.

Project ZomboidGame ModdingMultiplayerOpen Source

Five months from idea to public release

I spent five months building PalmPilot, a Project Zomboid mod inspired by the handheld organizers of the late 1990s. I published it on August 3, 2026 after months of designing the interface, connecting its systems to the game, testing persistence, and refining the small details that make the device feel like part of the world.

The goal was not to add a decorative prop. I wanted the PalmPilot to be a genuinely useful survival tool that still felt believable inside Project Zomboid.

A complete handheld device

Each physical PalmPilot has its own identity, nickname, battery level, settings, saved data, and Snake high score. That information stays with the device when it is dropped, stored, traded, saved, or carried into another multiplayer session.

  • Named task lists with sortable checklist items
  • Multi-line memos for routes, coordinates, frequencies, and survivor notes
  • A working calculator and live in-game calendar
  • A playable version of Snake with a per-device high score
  • Removable batteries and approximately 24 in-game hours of continuous screen use
  • Equipped-hand and placeable 3D models
  • Rare procedural spawning in appropriate offices, electronics stores, pawnshops, homes, and zombies

Making Beam work in multiplayer

One of the most important systems is Beam. Nearby survivors can transfer a task list, a memo, or all saved information between PalmPilots. Transfers are server-authoritative, validate distance and floor level, and update previously received entries instead of creating duplicate data.

Getting synchronization right taught me how quickly a feature becomes more complex when multiple players, inventories, physical items, and persistent state all need to agree.

Designing for the game world

I paid attention to the details around the main applications: battery drain stops when the interface closes, devices can be attached to a belt slot, hardware buttons work as shortcuts, Beam can be disabled for privacy, and spawn rates follow the game’s Other Loot sandbox setting.

The project became an exercise in making interface design, gameplay balance, persistence, and multiplayer networking feel like one coherent object.

What the project taught me

Building PalmPilot over five months strengthened my understanding of stateful UI, data persistence, multiplayer validation, debugging, compatibility, and designing software around real user behavior—even when those users are trying to survive Knox Country.

The mod supports Project Zomboid Build 42.20 or newer in both single-player and multiplayer, requires no dependencies, and is available through the PalmPilot GitHub repository.

Source documentation

Repository README

View on GitHub
PalmPilot running inside Project Zomboid

Palm Pilots

A pocket-sized piece of 1998 for the end of the world.

Bring a fully functional handheld organizer into Project Zomboid—plan supply runs, write survivor notes, check the date, crunch numbers, play Snake or Chess, and beam data to nearby survivors.

Project Zomboid Version Multiplayer Steam Workshop

Features · Installation · Controls · Multiplayer


Knox Country has no app store, no cell service, and very few working luxuries. Fortunately, your PalmPilot doesn't need any of them.

Features

Get organized Useful tools Authentic survivor tech
✅ Named task lists and checklist items 🧮 Working calculator 🔋 Removable batteries
📝 Multi-line memos 📅 Live in-game calendar 🕹️ Playable Snake and Chess games
🔎 Find and sort saved entries 📡 Infrared Beam transfers 🎒 Equipped-hand 3D model
💾 Data saved per physical device ⚙️ Nickname and privacy settings 📦 Placeable world model

Every PalmPilot has its own identity, battery level, nickname, settings, tasks, memos, Snake high score, and Chess position. Its data stays with the device when it is dropped, stored, traded, saved, or carried into another multiplayer session.

Built-in applications

To Do

Create named lists, add checklist items, mark jobs complete, and sort everything by name or creation date. It is perfect for loot routes, safehouse chores, and the ever-growing list of things that can kill you.

Memo

Keep multi-line notes directly on the device: generator locations, radio frequencies, map coordinates, suspiciously specific final words—you decide.

Calculator & Calendar

Use a functional calculator and check the current in-game date and time without breaking immersion.

Snake

The classic time-waster, now available during the apocalypse. While you actively play, Snake slowly reduces your character's Boredom and Unhappiness (the stat behind Depression). In multiplayer, the server applies and syncs this benefit. Pausing, leaving the game, or running out of battery stops it. Your high score belongs to the device, so think twice before lending it out.

Chess

Chess opens with Continue solo game, New solo game, and New multiplayer game. In the solo game, play White against a compact computer opponent. Tap a piece to highlight it and its legal destinations, then tap a destination. The computer pauses briefly before moving its piece across the board. Captured White pieces appear left of the board; captured Black pieces appear right. The game supports check and checkmate, castling, en passant, pawn promotion, stalemate, and the fifty-move draw rule. The solo position and captured pieces are saved on each physical PalmPilot, so you can close it and continue later. Older saved positions infer captured pieces from the board where possible.

For two-player Chess, both survivors need a powered PalmPilot in hand with Beam enabled. Choose New multiplayer game, select a player within 3 tiles on the same floor, and wait for them to accept. The inviter plays White, and each player sees their own pieces at the bottom of the board. The server checks every move. Leaving, putting a PalmPilot away, losing power, or moving out of range disconnects the match. The remaining player sees a Disconnected screen with a button to start a new multiplayer game. Live matches do not overwrite either player's solo save and cannot be continued after disconnecting; Continue solo game opens only the saved computer game. Active Chess play slowly reduces Boredom and Unhappiness at the same rate as Snake; multiplayer applies the benefit on the server. The benefit stops after 30 seconds without a tap or when you leave Chess. This is an original in-mod game; the ChessGenius Palm OS .prc is not included or executed.

Beam

Send one task list, one memo, or Beam All to copy everything to a nearby PalmPilot. Repeated transfers update previously received entries instead of filling the device with duplicates.

Multiplayer & Beam

Beam transfers are server-authoritative and validated before any data changes hands.

  1. Both survivors need a PalmPilot nearby on the same floor.
  2. Open Beam and choose a device or player.
  3. Select a task list, memo, or Beam All.
  4. The receiving PalmPilot stores its own local copy.

Beam can be disabled in the device settings whenever a survivor wants a little post-apocalyptic privacy. Opening devices, synchronization, and transfers support Build 42.20's multiplayer inventory behavior.

Finding a PalmPilot

PalmPilots are intentionally rare. Search places where late-1990s professionals and electronics are likely to have left them:

  • Executive and ordinary office desks
  • Electronics stores and electronics crates
  • Pawnshop display cases
  • Wealthy home offices
  • Office-worker zombies, who visibly carry the device in one hand

Use the Palm Pilots → PalmPilot Spawn Rate sandbox setting to choose None, Very Rare, Rare, Normal, or Common independently of higher Other Loot rates. The default, Original Behavior, preserves the previous spawn rates: containers follow Other Loot and half of office-worker zombies carry a PalmPilot. Very Rare gives roughly one-tenth of the Normal container rate and 5% of office-worker zombies; Rare gives roughly three-tenths and 15%. Setting Other Loot to None still prevents natural PalmPilot spawns. Restart the game or server after changing this setting. It affects only new loot and newly spawned zombies, not devices already in the world.

Battery life

A PalmPilot accepts standard removable batteries and runs for roughly 24 in-game hours of continuous screen use on a full charge. Closing the interface stops active screen drain, so switch it off when the horde arrives.

Controls

Action Control
Open Double-click the item or choose Open PalmPilot
Move the interface Drag the PalmPilot's top bezel
Close Press Space, Escape, or the power button
App shortcuts Use the physical hardware buttons
Move in Snake Arrow keys or the on-screen controls
Hotbar use Attach it to a belt slot and press that slot's number

Installation

Steam Workshop

  1. Open the Palm Pilot Workshop page.
  2. Select Subscribe.
  3. Enable Palm Pilots from Project Zomboid's Mods menu before loading your save.

Manual installation

  1. Download or clone this repository.
  2. Copy Contents/mods/Palm Pilots into your local Zomboid/mods directory.
  3. Enable Palm Pilots in the in-game Mods menu.

On Windows, the final folder will normally look like:

C:\Users\<your-name>\Zomboid\mods\Palm Pilots\

Compatibility

Game version Project Zomboid Build 42.20 or newer
Mod version 1.2.1
Modes Single-player and multiplayer
Dependencies None
Mod ID PalmPilots
Item ID PalmPilots.PalmPilot

Feedback & bug reports

Found a bug, balance issue, or a delightfully era-appropriate feature idea? Open an issue in the repository issue tracker or leave feedback on the Steam Workshop page.


Plan the run. Write it down. Beam it over. Try not to get bitten.

Palm Pilots is a community-made mod and is not affiliated with The Indie Stone or Palm, Inc.