Hi @Md Sohel Khan,

If I am not mistaken, the timeout problem is being caused by your document binaries.
Binaries are large and take more time than usual for any database operation, as you are aware.

You can try with offline sync method: implementing_offline_sync

There are some best practices that help optimize syncing time, which you can refer here: synchronization_on_mobile_devices/

Hello Sohel,

Syncing binary data of documents will take long time especially if document size is big and you have high number of records that you are syncing.

I would recommend to sync all details into document table except binary data of document itself so you can display all document information on screen of your mobile data from local storage and once user click on a specific document to open or download you can query binary data of this document from server using document Id 

Hello Sohel, 

As per OutSystems best practices & approach make sure that the local entities have only those attributes which are use for offline business logic requires and do not add all the attributes of the server entities. 

Also, Do not load all data from server to local. update only those records that are relevant to the current user of the mobile application.   

Please follow the checklist for offline sync from the OutSystems.

https://success.outsystems.com/documentation/11/developing_an_application/use_data/offline/offline_sync_checklist

I hope it will help to your sync logic and approach. 

Thanks