Logging library for Arduino that can output to both Serial and File with one line
DebugLog can output level-controlled logs to both Serial and File with one line at the same time. It also supports variadic arguments, log level control, assertion, manual file flushing, etc.
This library is compatible with all architectures so you should be able to use it on all the Arduino boards.
To use this library, open the Library Manager in the Arduino IDE and install it from there.