https://devzone.nordicsemi.com/f/nordic-q-a/20451/android-app-for-external-mcuHi, I want to OTA firmware upgrade of STM32 (External MCU) using nRF51 through Android App on BLE. STM32 and nRF51 communicate on UART. Please any one suggests how to use nRF connect or Master Control Panel for that. please provide steps if availableen-USTelligent Community 13Thu, 16 Mar 2017 11:40:18 GMThttps://devzone.nordicsemi.com/thread/79739?ContentTypeID=1Thu, 16 Mar 2017 11:40:18 GMT137ad170-7792-4731-bb38-c0d22fbe4515:0f4f0d4f-68d8-4e88-9aa9-064823d5cf54dc<p>I think we make our custom Android app that is only solution.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/79741?ContentTypeID=1Wed, 15 Mar 2017 13:25:50 GMT137ad170-7792-4731-bb38-c0d22fbe4515:241b9ddf-dc8d-45ad-a3ae-7271a53bcc16FormerMember<p>Unfortunately, I don&#39;t think we have any apps that takes a file as input and then the file to bytes..</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/79740?ContentTypeID=1Wed, 15 Mar 2017 10:56:14 GMT137ad170-7792-4731-bb38-c0d22fbe4515:add40b65-79ed-48f3-9282-25aff2a335f4dc<p>Hi,</p> <p>Thanks for reply!!</p> <p>is it possible to pass file and nRF Toolbox convert into multiple packets(20 bytes per packet)? OR do I need to create manually one by one packets?</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/79738?ContentTypeID=1Wed, 15 Mar 2017 10:17:07 GMT137ad170-7792-4731-bb38-c0d22fbe4515:701e7a77-5f4e-4249-83bc-ff59fc4a22b0FormerMember<p>Unfortunately, we don&#39;t have an app that do exactly what you want. Perhaps you can use the <a href="https://github.com/NordicSemiconductor/Android-nRF-Toolbox">nRF Toolbox --&gt; nRF UART source code</a> as a starting point?</p><div style="clear:both;"></div>