ios how to record data manipulation

I now want to record data manipulation ios used to ask what records there ios no log file (built-in) or directly read and write files directly io
Reply:
1, sqlite
2, userData
3 files
Reply:

cited a floor reply:

1, sqlite
2, userData
3 files

Obj-c files using the built-in designed for logging it? For example: like java log files
Reply:
Log, then write their own documents.