I am arriving on an international flight at Bangkok Suvarnabhumi Airport (BKK) and saw the Fast Track service in the SAWASDEE by AOT app.
The app mentions an optional buggy service, but I am unclear on what the basic Fast Track service includes.
Does the basic service cover priority immigration only, or also meet-and-greet, airport escort, baggage claim help, or customs assistance?
This service has it's own dedicated website - https://www.sawasdeepass.com/
This website describes what is included in this service, for both arriving and departing passengers.
What is not well covered by this website is the "Fast Track" service at immigration - in both cases this service involves a dedicated immigration area (and dedicated security, for departure), which normally has a much shortly line (if any) than the normal security/immigration area.
Note that SAWASDEE Pass (sometimes referred to as "SAWASDEE by AOT", where AOT refers to the 'Airports of Thailand') is the only product that can provide these services. This service can be purchased via multiple channels, including direct from the website above, via the 'SAWASDEE By AOT' app, or via a number of third parties like Pelago, Tripadvisor or Klook - however if purchasing via a third party website be sure to purchase the "SAWASDEE Pass" product, and be aware that there are normally extra steps required to redeem/book the service when going via these channels.
The Thailand Police have recently warned of a number of other fraudulent services claiming to provide similar services - these should be avoided unless they are reselling the above product as they are likely fraudulent in some way or other.