I was tired of searching the issues of the arduino - esp32 core repo for problems and solutions and started to build up a Wiki for this repo.
I try to keep it up to date daily, whoever wants to contribute is welcome.
You can see a list of current entries here: Arduino core for ESP32 Wiki
I started as well to add some demo code for WiFi, Bluetooth, BLE, TCP and UDP communication on my website.
Maybe it is helpful for some one.
http://desire.giesecke.tk/index.php/2018/01/30/enable-log-levels-in-platformio/
Please correct this page because we don’t use platform.txt file. “Set log level for a specific project” is the right solution.
P.S: I added link to our documentationhttp://docs.platformio.org/en/latest/platforms/espressif32.html#arduino-core-wiki
Thanks for adding a link to the repo.
If I understand you correct, only method 3 is working on PlatformIO? I don’t mention platform.txt anywhere, so I am not sure what you mean with that.
Ok, corrected it now. Thanks for pointing to this wrong info.
The link to the wiki is broken 
Yeah well
The end of Desire.Giesecke.TK
I am very sorry to the open source community, but some brainless hackers found it funny not only to misuse my website but at the end delete the complete content.
But, just use the wayback machine?
still there.