> For the complete documentation index, see [llms.txt](https://assetstore.essentialkit.voxelbusters.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://assetstore.essentialkit.voxelbusters.com/features/cloud-services/playmaker/use-cases/use-case-2-multi-device-sync.md).

# Multi-Device Progress Sync

## Goal

Load saved data when app starts and listen for changes from other devices.

## Actions Required

| Action                         | Purpose                                 |
| ------------------------------ | --------------------------------------- |
| CloudServicesGetValue          | Load saved data                         |
| CloudServicesOnSavedDataChange | Listen for remote updates               |
| CloudServicesGetChangedKeys    | Read changed key list (optional helper) |

## Variables Needed

* playerLevel (Int)
* totalScore (Int)
* changedKeys (Array: String) - PlayMaker Array (set element type to String)
* changeReason (Enum: CloudSavedDataChangeReasonCode)

## Implementation Steps

### 1. State: LoadProgress (On App Start)

**Action:** CloudServicesGetValue

* **Inputs:**
  * key: "player\_level"
  * valueType: Int
* **Outputs:**
  * value → playerLevel

Repeat for each key you want to load.

### 2. State: ListenForChanges

**Action:** CloudServicesOnSavedDataChange

* **Outputs:**
  * changedKeys → changedKeys array
  * changeReason → changeReason
* **Events:**
  * dataChangedEvent → HandleRemoteChange

### 3. State: HandleRemoteChange

Use the `changedKeys` array from `CloudServicesOnSavedDataChange` directly, or call `CloudServicesGetChangedKeys` to fetch the same cached list in a later state. Loop `keyIndex = 0..changedKeys.Length-1` and read each key using PlayMaker Array Get.

1. If you need conflict handling, call `CloudServicesGetCloudAndLocalCacheValues(keyName)` to get both values:
   * decide your policy (cloud wins / local wins / max wins / prompt user)
2. Otherwise, just reload from cloud:
   * If keyName == "player\_level" → `CloudServicesGetValue("player_level", valueType:Int)` and update `playerLevel`
   * If keyName == "total\_score" → `CloudServicesGetValue("total_score", valueType:Int)` and update `totalScore`

If you don’t want a loop, you can also directly use PlayMaker Array actions (Array Get / Array Contains) on `changedKeys`.

## Conflict Resolution Strategies

**Last Write Wins:** Use remote value always **Highest Wins:** Compare local vs remote, keep higher value **Manual Merge:** Prompt user to choose