SPIFFS stands for Serial Peripheral Interface Flash File System.
If you are new to SPIFFS. The easiest way to explain SPIFFS is to see it as an onboard SD card where you can store files. Most commonly used for storing log and webserver(html, css, js img) files.
As mentioned in the iotappstoryloader page. You don't need to compile or upload SPIFFS to make IOTAppStory work. But from library v2.1.0 on you do need to select at least 64Kb of SPIFFS for storing certificates in the IDE board settings. These certificates are used for TLS(https) communication with IOTAppStory.com
HTTPS_8266_TYPEBefore library v2.1.0-RC3 the default for ESP8266 devices was to use a fingerprint instead of the certificate itself. You can change this in the config.h file by editing the HTTPS_8266_TYPE define.
If you don't plan on using SPIFFS skip the next part.
Compiling SPIFFSHow to setup your IDE and compile SPIFFS binaries is beyond the scope of this Wiki. (tutorial may follow in the future) But here are some quick pointers: Arduino IDE users need to install the fs-plugin for the 32 or 8226. And Platform IO users should follow the pio documentation for their platform.
Include certificatesIf you are going to compile and OTA update SPIFFS. Make sure to include the IAS root certificate. The IAS library expects it to be in the "cert" folder. You can download it here.