https://devzone.nordicsemi.com/f/nordic-q-a/40939/qeustion-data-send-errorHI, I am seungwoo I am developing data transmission using nrf52810. A 300-kilobyte file is divided into 220 bytes and transmitted continuously. 11-27 17:24:24.416 W 15138 lbs_tag_service woo send4 packetInteration = 212total = 1543 11-27 17en-USTelligent Community 13Wed, 12 Dec 2018 14:03:12 GMThttps://devzone.nordicsemi.com/thread/161471?ContentTypeID=1Wed, 12 Dec 2018 14:03:12 GMT137ad170-7792-4731-bb38-c0d22fbe4515:aa82b827-5837-4437-9636-b3cd88de9e69Hung Bui<p>Hi Seungwoo,&nbsp;</p> <p>Is this a duplicated case from this case:&nbsp;<a href="https://devzone.nordicsemi.com/support-private/support/218754">devzone.nordicsemi.com/.../218754</a> ?&nbsp;</p> <p>I would suggest to continue on the other case.&nbsp;</p> <p>Please be aware that we only handle the other side of the connection on the nRF5x side, we don&#39;t have any control over the Android implementation. We can try to help you to improve the performance but we can&#39;t fix the issue on Android phone.</p><div style="clear:both;"></div>