Debug your apps. Find error stacktraces. See what your phone is saying about you behind your back. It's all there in the system log, aka logcat!
MatLog shows a scrolling (tailed) view of the Android "logcat" system log, hence the goofy name. It also allows you to record logs in real time, send logs via email, and filter using a variety of criteria.
Color-coded tag names
Easy-to-read column display
Recording mode (with widget)
Save & open from SD card
Send logs as email or attachment
Auto-scrolls when at the bottom of the screen
Search autosuggestions & saved filters
Select and save parts of logs
Open-source and ad-free
^ Above copied from Nolan Lawson's original CatLog app's description.