I choose Grab mainly because I always have installed for GrabPay payments. Sometimes I use Gojek (often unloaded because my phone doesn't have much storage) because it's cheaper.

I avoid first-party taxi apps because they're shit and do dumb stuff like charge a 10% surcharge for credit card payments. They could get away with it 20 years ago, but I'm so glad Uber, Grab, and all the others are eating their lunch.