The differences between this modpack vs Prehistoric fossils is that I tweak and added many performance mods to make sure this modpack run smoothly on mobile 

this modpack integrates the Prehistoric Nature mod, plus its dimensions, and a few basic support mods added, Optimized for mobile this version ensures smooth gameplay so you can play anytime, anywhere

For optimal performance

we recommend to allocate at least 4GB RAM or more to run the modpack ideally

optifine
there should be no issue using optifine in this modpack"