[wrxtasy]

Kodi on the Shield does a very respectable job of upscaling from my experience. There's some great tips here:

https://github.com/koying/SPMC/wiki/Reco...ith-4K-GUI

Hi, you say Kodi on the shield does a great job of up scaling, then link to settings for SPMC...?

Most of those settings apply to both.

Yes the settings are in the same spot but you are kidding yourself if you think you are going to achieve high quality upscaling with Kodi Krypton's - Nearest Neighbour and Bi-Linear upscaling only algorithms vs Lancos3 - Optimised - SPMC uses at a 4K Android Resolution setting.

The other point is no other 1080p Android Apps gets to use SPMC high quality Lancos3 - Optimised when displaying 720/1080p content at a 2160p Android resolution. You are better as @DaMacFunkin said to leave everything at an Android res. of 1080p and only manually switch Android resolutions when you want to playback 2160p content. Particularly if you are not using SPMC.

Let modern 4K TV's handle 720/1080p > 2160p upscaling to produce a higher quality, sharper picture output for 720/1080p Android Apps and Kodi Krypton.

Ultimately the Android OS needs Auto, user selectable App - Resolution switching to achieve the highest quality results without PITA manual Resolution switching.
With LibreELEC for example on my 4K TV the Kodi GUI is left at 1080p and Auto Resolution switches only when I fed it 2160p content. My TV produces nice, sharp high quality 720/1080p > 2160p upscaling picture output.