Custom mobile task form enables offline approval for remote workers in field operations

BPM Appian
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1

We implemented a custom mobile approval solution for our field operations team who frequently work in areas with unreliable network connectivity. The challenge was enabling supervisors to review and approve equipment inspection tasks even when offline, with automatic synchronization when connectivity is restored.

Our solution uses SAIL forms with offline mobile capabilities to cache task data locally on the device. When supervisors open pending approval tasks while connected, the form data is stored in the mobile app’s local cache. They can then review inspection details, add comments, and submit approvals even without network access. The form includes conditional logic to detect offline status and queue the approval action locally.

When connectivity returns, the mobile app automatically syncs the queued approvals to the server and updates the process instances. We’ve also implemented conflict resolution logic to handle cases where the same task might be modified by multiple users or if the task status changed server-side during the offline period.

This has significantly improved our approval workflow efficiency - supervisors can now process approvals during site visits without waiting to return to connected areas. We’ve seen a 40% reduction in approval cycle time since implementing this solution.

2

This is a great use case! How did you handle the local caching mechanism? Did you use Appian’s built-in offline mobile features or implement custom local storage? Also curious about your conflict resolution approach - what happens if a task gets reassigned or cancelled while someone has it cached offline?

3

How did you handle authentication and security for offline operations? If a supervisor’s device is offline for an extended period, how do you ensure their session remains valid when they try to sync? Also, are there any data encryption considerations for sensitive approval data stored locally on mobile devices?

4

Great points on security. Here’s our complete implementation approach that addresses all these concerns:

Offline-enabled SAIL forms architecture: We built the approval form using SAIL with specific offline capabilities enabled in the interface definition. The form structure uses a!formLayout() with saveInto parameters that write to local variables when offline. Critical components include:


// Pseudocode - Offline form structure:
1. Check connectivity status using a!isOffline()
2. If offline, store form data in local cache with timestamp
3. Display offline indicator banner to user
4. Enable form submission that queues to sync queue
5. On submit, validate required fields locally
// Actual sync handled by Appian Mobile framework

Local data caching and sync mechanism: We configured the mobile app to pre-cache tasks assigned to each supervisor when they’re connected. The caching strategy includes task metadata, related inspection data, and approval options. The sync queue operates on a priority system - approvals sync before comments, comments before attachments. The mobile framework handles the actual sync timing, but we added custom logic to detect sync failures and retry with exponential backoff.

Conditional logic for error handling: This was crucial for user experience. We implemented multiple layers of error handling:


// Pseudocode - Error handling flow:
1. Pre-sync validation: Check if task still exists and is assigned to user
2. Conflict detection: Compare local version timestamp with server version
3. If conflict detected: Present options (discard, force submit, escalate)
4. Network error handling: Queue retry with notification
5. Post-sync verification: Confirm server accepted changes
// Log all errors to sync audit trail

For authentication, we use OAuth tokens with 7-day validity specifically for mobile offline users (versus 24-hour tokens for web users). The mobile app securely stores refresh tokens in iOS Keychain or Android Keystore. When syncing after extended offline periods, the app automatically refreshes the authentication token before attempting to sync cached data.

Data encryption follows platform-specific best practices - we enable iOS Data Protection for all cached files and use Android’s EncryptedSharedPreferences for storing sensitive approval data. The encryption keys are tied to device biometric authentication, so cached data is only accessible after user authentication.

One implementation detail worth noting: we added visual indicators throughout the form to show connectivity status and sync state. Users see clear badges showing how many approvals are pending sync, and they receive notifications when syncs complete successfully or require attention. This transparency significantly improved user confidence in the offline capability.

The business impact has been substantial - not just the 40% reduction in approval cycle time, but also improved data quality since supervisors can complete approvals immediately while details are fresh, rather than waiting until they return to connected areas. We’ve processed over 3,000 offline approvals in the past six months with a 99.2% successful sync rate.

5

Good question about multimedia. We initially included photos in the offline cache but ran into storage constraints on older devices. Our solution was to implement tiered caching - only the essential approval data (inspection results, comments, approval decision) is cached offline. Photos and videos are marked for delayed upload and stored separately in the device’s media storage. When connectivity returns, the approval syncs first (high priority), followed by the multimedia attachments (lower priority background sync). This keeps the offline form lightweight while still capturing all necessary data.