I've tried to use rust on mobile apps, but type conversion & manual memory management does make using it really hard and unappealing. Did you find a better way using rust that mitigate theses kinds of problems ?

It all depends on your integration point and use case. The extra interopability work has to pay for itself. One possible trick is to use a message passing architecture and pass json/protobuf messages between the code bases.

Some companies also use lots of ffi code generation tools.