There are two main options in Bangkok.
Grab and Bolt:
Grab App covers a lot of things, including food orders etc.
On the Grab App there is the transport option and you can select the type of Transport from ‘JustGrab’ which is any, including regular taxi or a car
‘GrabTaxi’ which is a taxi.
‘GrabCar premium’....
‘GrabCar for Ladies'
‘GrabBike - win’ (motorcycle)
‘Grab SUV’ and ‘Grab XL’
Grab accepts Cash and local credit cards (I’ve never tried with int’l credit cards).
Bolt only accepts Cash and also has a few variable options from Taxi, car, premium, motorcycle etc
IMO: Grab is better than Bolt - but lately, in the awful weather its been difficult to get a Grab.
Bolt seems more difficult to secure.