If uber built these no one will question them why don't they use some off the shelf solution. Gojek is a google cloud customer and under their startup program - surge. So I am sure they are aware of the solution proposed.
They don't call themselves technology company but company which helps gojek drivers to find jobs and earn extra. In the process they became a food delivery, transportation, payments, courier company. In spite of this they still focus on their primary objective to find jobs for gojek and let them earn extra for better living.
Before Gojek app most of the drivers were just idling waiting for passengers, now with a $25 Kai OS feature phone [1], they can just receive a message and earn instead of just idling, they don't have to use iPhone or Android or some heavy OS. Indeed based on social survey some of the drivers could increase there earning 3-4 times based on how willing are they to take up additional jobs.
I believe the beauty of Gojek lies in its model to focus on finding jobs and developing solution to help those motorcycle drivers using technology. Although they extended it to cars. I am intrigued by their idea since its not a copy of Uber, but a solution to a problem local to Indonesia, which can extend to any country in the world finding jobs to do while idling and earn more.