I believe this wrapper has support for both Android and iOS https://github.com/pegli/ti_touchdb
Note that there is no official support for Titanium so if you have any questions about this wrapper, you might have more luck if you open an issue there.
Additionnally, we’ve started experimenting with React Native on Android and you can take a look at the screencast and tutorial here http://blog.couchbase.com/2015/november/live-reload-with-react-native-and-sync-with-couchbase-mobile
James