https://devzone.nordicsemi.com/f/nordic-q-a/8542/multiple-data-on-single-characterstics-data-write-notify-from-peripheral-using-ble_app_uart-appicationHi All, I&#39;m using ble_app_uart Application to send some notifications from Peripheral to central device. I&#39;m using API ble_send_string() to send notifications to other Mobile APP. When i test this setup on nRF UART App, it works fine, nRF App showsen-USTelligent Community 13Thu, 06 Aug 2015 18:36:06 GMThttps://devzone.nordicsemi.com/thread/31236?ContentTypeID=1Thu, 06 Aug 2015 18:36:06 GMT137ad170-7792-4731-bb38-c0d22fbe4515:8ee93c85-eab4-4edf-8ddc-a969972ee6bfBrajesh<p>Thank you so much Aleksander. It was really helpful to have this info to clear doubt, looks like we might have to look into the source code if nRF UART App and will have to fix our android app for the same.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/31235?ContentTypeID=1Thu, 06 Aug 2015 12:29:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b73de881-aaf3-4238-be93-553d93dea860Aleksander Nowakowski<p>Hi, no, we do not filter anything. It must be something in your Android application. It looks like you may have multiple listeners attached or some race conditions. Please check if you get the onCharacteristicChanged ones or multiple times. If multiple, check if the BluetoothGatt object is the same. Maybe you are connected multiple times to a single device.</p> <p>The source code of nRF UART v2 is available on our website. I think you need to log in there. You may also check the UART profile in nRF Toolbox app: <a href="https://play.google.com/store/apps/details?id=no.nordicsemi.android.nrftoolbox">play.google.com/.../details</a> The source code for this app is available on GitHub: <a href="https://github.com/NordicSemiconductor/Android-nRF-Toolbox">github.com/.../Android-nRF-Toolbox</a> (DFU Libary project is also required if you want to compile it on your own).</p><div style="clear:both;"></div>