Although a computer is better, there might be great potential for smartphones to participate in the swarm. But there seems to be some complications.
https://gitlab.com/proninyaroslav/libretorrent/-/issues/2
Someone did make a torrent client for iOS 16+ devices named ‘iTorrent’ but there is no mention of I2P.
For those curious, here is an I2P guide from 2 years ago.
https://lemmy.ml/post/1295873