I've got an alternative implementation of slf4j-android that you may be
interested in: https://github.com/lp0/slf4j-android

It has various features and configurability (which makes it more of a logging
framework than a simple adaptation layer) as the Android logging is quite
basic.

It avoids the issue in #204 and caches calls to the native isLoggable() method.

Minimal configuration to specify a default logging tag is usually required to
conform to existing Android conventions (using a minimal number of logger
names).