My model is a "49PUS7150" Some time ago someone asked if it was possible to get the chromecast backdrop(the random picture gallery) to show since some Philips TVs has a built in chromecast and Android tv software.
I found a solution to this problem.
First you need to go into settings->general settings->Android settings. Then open "about" and go down to "build" and press ok repeatedly until you become a developer. Press back and go down to "Developer options" under the "preferences" section. Under "general" turn "stay awake" to "OFF". This will otherwise prevent daydream from starting.
When this is done you essentially need three apps. Links are posted in the end. You sideload all these with ES File explorer or any other way that suits you.
The first app is of course "backdrop daydream" from Google.
Then you need "Aerial dream" since this enables you to go into the system menu where you can activate daydream mode on your Philips TV. Open the Aerial dream after installation and scroll all the way down to "open system screensaver options" select daydream and press ok. You're in! Switch the slider on the right to turn daydream mode on. Choose backdrop as your preferred daydream screensaver. Up in the right hand corner press the three dots and under "when to daydream" select the option "either". Now press back then the three dots again and press "start now" to see if it all works.
Last you need "screen timeout" to set the time delay for daydream to start. I suggest you first set it to 5 seconds and go back to main Android tv menu and wait for it to start. If you only get a black screen (happened for me) then uninstall "screen timeout" the timeout is still going to be 5 seconds without the app installed. Then it worked for me. Reinstall "screen timeout" and you can now set it at any time you want.
That's it. Good luck!
https://m.apkpure.com/aerial-dream/com.codingbuffalo.aerialdream
https://m.apkpure.com/screen-timeout/de.lhoer0.screentimeout
I may have to try this. But the last time someone forced the screen saver they had some major problems.....but I can’t remember what they were.