There are two events in game that cause severe frame drops when they shouldn't.
First off are particles, most notibly in the Ender Dragon fight. I play on an LG Aristo, which isn't an old nor underpowered phone. When the Ender Dragon uses it's fireballs the game suffers a severe frame drop (from 60 down to 1-5 fps), making the game unplayable. Perhaps add an option to reduce particles, or even just optimize them better?
The same issue arises when near other players. I play on my friend's realm alot, and whenever we go mining together, there are pleanty of situations where we're close to eachother. If I even have them visible at the edge of my screen and we're less than a block apart, my fps begins dropping. It gets worse when they're wearing armor, and even worse if they get closer. Doesn't happen with mobs at all from my experience.
Thank you for your report!
However, this issue has been closed as a Duplicate of MCPE-18171.
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