Hardware transform vs Ubershaders

[Magichost]

Are Ubershaders too demanding for weak phones and can't I use hardware transform (less demanding?) to do the same thing as Ubershaders?

[LunaMoo]

Those aren't even close to being the same things.

Hardware transform is just a name for doing some computations on the GPU.

Graphics in PSP games can't be directly ran on modern hardware, hence you have to program everything yourself to run on gpu - shaders are used for that.
Unfortunately when you have a lot of variations of many basic effects they often change and need to compile when they show up the first time, this causes shader stutter.

Ubershaders is a name for a shader that combines those tiny variations into one/few large shader/s with branches to include as many cases as it can so then the shader is compiled and doesn't have to recompile when game slightly changes something removing shader compile stutter. Unfortunately this also makes much more complex shader/s running all the time instead of tiny ones generated on the fly and as such reduces performance a lot on weak/old gpu's especially mobile ones.

Ubershaders on low end devices were causing severe slowdowns and were really unwanted by people on those devices, you have a choice between accepting being a lower end hardware user, upgrade or wait XX years for low end being powerful enough, but by then something else might exist that will also not work on future low end hardware.

I'd recommend to just lower your expectations until you get into position where buying more powerful hardware for your hobby isn't ruining your budget. 99% of PSP games are perfectly playable with minor stutter here and there, it was never a hardcore gaming platform, most games are designed with poor controls in mind and are easy.