grab works really well in Bangkok, fast and simple. Another advantage of grab is that you indicate directly where you want to go, you are sure to arrive at your destination. Unlike taxis, or between our accent, the taxi driver's poor understanding of English, I have already thrown in the towel after a while by dint of going around in circles without being able to get where I wanted.
sometimes the best is to mix public transport and grab: a part in skytrain to avoid the big traffic jams, get out at a station where there are not many people and order your grab. Be careful not to order a grab in congested places: galley guaranteed. and also choose the side of the ideal road, it sometimes takes 20min by car, to find yourself on the other side of the road (2min on foot 🙂