I’ve spent a large part of today testing how fast every Fire TV model can launch apps for a performance benchmark article I plan to put up on Monday. Something I immediately noticed is that Netflix launches fast. Like, very fast. Actually, it launches too fast. From a fresh reboot of the device, most apps take several seconds to launch. Netflix, on the other hand, launches in 1 to 2 seconds every time. It shouldn’t be launching that fast when the device was just rebooted because there shouldn’t be any apps in memory (RAM). After a bunch of testing, I’ve determined that Amazon is preloading Netflix into memory on Fire TV devices before it is ever launched, making it load faster when/if you do decide to launch it. Amazon is not doing this for other apps, including Prime Video.

When an app is launched for the first time after a reboot, after many other apps have been used, or after the device has been idle for a while, the app needs to be read from the device’s internal storage and loaded into the device’s memory. This is often referred to as a cold launch. Once an app has been loaded into memory, and assuming nothing else has kicked it out of memory, it will launch much more quickly the next time you go to launch it. This is often referred to as a warm launch. It appears as though Amazon is preloading some or all of Netflix into memory, or pre-warming the app, on certain Fire TV devices. The result is that the first time Netflix is launched, it launches as fast as if it was recently launched and still in memory.

To be clear, this is only the case if you’ve chosen to install the Netflix app in the first place. Amazon is not pre-installing Netflix, so if the app has not been installed by you, then this change has no effect on the Fire TV. It only affects Fire TV devices that have chosen to install Netflix.

Here are launch times, in seconds, for Prime Video, Netflix, Disney+, and Hulu on the Fire TV Stick 4K Max:

I tested those four apps because they are the four app shortcut buttons on Fire TV remotes in the US. All times were measured from launch to reaching the app’s profile selection screen or home screen, whichever came first. For cold launch times, I force-quit the app, to ensure it was not in memory, and measured how long it took to launch. For warm launch times, I loaded the app, pressed the home button on the Fire TV remote to leave the app, and then measured how long it takes to immediately relaunched the same app. For reboot launch times, I rebooted the Fire TV, waited a few seconds after it fully loaded the home screen, and then measured how long it takes to launch the app. I took an average of 3 measurements for each value.

As you can see, cold launch times for all apps but Netflix are similar to the app’s reboot launch times, as they should be. Netflix, on the other hand, lanches nearly as fast after a reboot as it does when the app is warm, indicating that the Fire TV is giving the Netflix app some kind of preferential treatment in order to launch it faster than it should be launching.

It’s worth noting that reboot launch times for the other 3 apps are likely slower than the app’s cold launch time because the Fire TV is still busy performing background tasks after a reboot. Whereas, for the cold times, the Fire TV had been sitting idle for a while. It’s also worth mentioning that Disney+ has a poor warm launch time, relative to the other apps, because it always plays the full Disney logo animation when it’s launched, while the other apps skip right to the profile selection screen or home screen if the app is warm and in memory.

At this point, I was already convinced the Fire TV was preloading Netflix on boot, but to prove it further I ran another test. I botted up the Fire TV Stick Max and measured that about 610 MB of its 2 GB of memory was not being used after the device had sat idle for a while. I then connected to the device, using the Android Debug Bridge (ADB), and remotely force-quit Netflix (which I never launched) using a shell command. Immediately after running the quit command, the available memory increased to 695 MB instantly. I then launched Netflix and saw the available memory drop to around 601 MB.

I did not check every Fire TV model for this behavior with Netflix, but I did observe it on the aforementioned Fire TV Stick 4K Max and on the 2nd-gen Fire TV Cube. I did not see the same behavior on the original Fire TV Stick 4K. This could be because only Fire OS 7 devices behave this way with Netflix, which the Stick 4K Max and Cube are, while the older Stick 4K is a Fire OS 6 device. It also seems like some Roku devices preload Netflix this way as well, but Roku does not provide the level of control and insight into what the device is doing to know for sure. I did not test Apple TV, Android TV, or Google TV devices.

On one hand, it makes sense for Amazon to want the world’s most popular streaming app to launch as fast as possible, since so many people will benefit from it launching faster. On the other hand, I’d much rather have control over which apps, if any, receive this kind of special treatment, instead of it being decided for me. One unknown is whether Amazon is voluntarily doing this or if Netflix is forcing them to do it through the leverage they hold as the top streaming app.