For all Android targets the main issue is trying to support the client use of libraries (C library, C++ library, etc.). The private loader approach is made difficult due to Android's hidden interfaces. A client that either does not use libraries at all (only DR API) or statically links all its libraries into itself (and redirects malloc via wrap) would avoid this issue for typical usage. (
https://github.com/DynamoRIO/dynamorio/issues/7312 is a proposal for a long term solution.)
Help on improving support here would be appreciated by the community.