Regression - Scheduler Drag & Drop Fails on Samsung Galaxy Tab S9 FE

[Andrzej Stach]

Hi,

I'd like to report a new issue that I noticed after updating to the version that fixed the touch scrolling problem reported in my previous support ticket forum. The scrolling issue has been resolved, but another problem seems to have appeared.

Environment

• Syncfusion.Blazor.Schedule (latest version tested)

• Blazor Server (.NET 10)

• AllowDragAndDrop="true"

Problem

On a Samsung Galaxy Tab S9 FE, drag-and-drop no longer works. The drag operation never starts, so appointments cannot be moved.

The same application worked correctly on this device before updating Syncfusion to the version containing the touch scrolling fix.

I also tested the official Syncfusion demo, and the issue occurs there as well:

https://blazor.syncfusion.com/demos/scheduler/external-drag-and-drop/

Additional information

• Works correctly on desktop browsers.

• Works correctly in Chrome Device Emulator.

• Works correctly on Android phones and on the iPad that I tested.

• Fails on the Samsung Galaxy Tab S9 FE in both my application and the official Syncfusion demo.

• So far, I have only been able to test on this particular tablet model, so I cannot confirm whether the same issue affects other Android tablets.

Could you please investigate whether this might be a regression introduced after the recent Scheduler changes? If needed, I'd be happy to perform additional tests.

Regards,

Andrzej

[Saritha Sankar]

Hi Andrzej Stach,

Your reported problem is considered a bug. The fix for this defect will be included in our upcoming weekly patch release, which is expected to be rolled out on August 18, 2026. You can track the status of the fix at the following link:

 

Feedback : Scheduler Drag & Drop Fails on Android Tablet device in Blazor | Feedback Portal
 

Disclaimer: Inclusion of this solution in the weekly release may change due to other factors including but not limited to QA checks and works reprioritization.

Regards,
Saritha S.

[Saritha Sankar]

Hi Andrzej Stach,

We are glad to announce that our weekly release (V34.2.4) has been rolled out successfully. The fix for the issue has been included in our weekly release(34.2.4). Upgrade to the latest version to resolve the issue.

Release notes: Essential Studio® for Scheduler SDK Release Notes

Feedback: Scheduler Drag & Drop Fails on Android Tablet device in Blazor | Feedback Portal

Root Cause: This issue occurs due to a timing difference in gesture handling. The Touch module uses a 750 ms delay to detect a tap-and-hold action. However, on the Galaxy Tab S9 FE, the touch move event is triggered very quickly and cancels the pending tap-and-hold detection before it completes. As a result, the expected tap-and-hold action is not executed.

Sample: https://blazorplayground.syncfusion.com/hjVHtvWOCOfkKHHt

We thank you for your support and appreciate your patience in waiting for this release. Please get in touch with us if you would require any further assistance.

Regards,
Saritha S.

[Andrzej Stach]

Hi Saritha,

Thank you for the information and for fixing this issue.

I have updated to the latest version and tested the Scheduler on the Samsung Galaxy Tab S9. Everything now looks good - drag and drop is working correctly again.

Thanks again for your support and for resolving the issue.

Regards,
Andrzej

[Saritha Sankar]

Hi Andrzej,

Thank you for the update and for confirming the fix.

I'm glad to hear that after updating to the latest version, the Scheduler is working correctly again on the Samsung Galaxy Tab S9 and that the drag-and-drop functionality has been restored.

Kind regards,
Saritha