It is this developer options menu where I expected to find an option to enable ADB Debugging or the installation of apps from unknown sources, as is available on all prior Fire TV devices, but the Echo Show 15 only lists one developer option called Ship Mode, which just resets the device to factory defaults. While this developer menu has been available since the original 1st-gen Echo Show was released in 2017, it has served no practical purpose since there has not been a way to use 3rd-party apps on Echo Show devices prior to the arrival of the new Fire TV capabilities. Like stand-alone Fire TV devices, the Echo Show 15 has a hidden developer options menu, which can be accessed by tapping the device’s serial number display under Settings > Device Options. As a Fire TV app developer myself with dozens of apps that have been installed tens of millions of times, this choice by Amazon, essentially, ties my hands behind my back and leaves me with no way to easily make my apps compatible with the Echo Show 15. On the Echo Show 15, neither option is available, leaving developers no way to test their apps directly on the smart display.

On all Fire TV devices prior to the Echo Show 15, app developers could test and debug their apps by sideloading them through the Android Debug Bridge (ADB), as outlined by Amazon’s developer documentation, or by using another app to sideload their app, like my Downloader app.

See here for a full guide on how to sideload apps on the Echo Show 15.

A workaround method for sideloading on the Echo Show 15 has been discovered.

Plex echo show