This app, by the way, is available in iTunes and the Google App Store for Android users. Before you can start using it, it will ask you to register an account connecting it to your phone number and email address where they will send your booking details.
You will need to have a reliable 3G/LTE signal while doing this which I was lucky to have with Globe yesterday. If your connection isn't very good, you can opt to book while you are still in a coffee shop or a restaurant while using the establishment's wifi. ^^
Now, you will not always find the exact location where you want to be picked up nor the place where you want to go. For cases like this, you can always add a note so the driver can easily find you.
The nifty part is you get to see the information of the cab and the driver that gets assigned to you. As of the moment they are working on having Grab Taxi logos on participating cabs but for now, you can always check the plate number of the cab before you get in it.
The app also has a Call Driver feature that uses your existing network to make a call. If you are using a prepaid account, make sure that you have credits before using this feature.
For added security or if you are the type that just wants to share every little detail of your life with people on social media, you have the option to share your cab and destination information.
Note: First 2 screenshots were taken at a different time to illustrate the complete process.
If you happen to miss your cab because you don't want to go out yet until you are sure that the cab is already out waiting for you, you will get an SMS notification asking you to call the driver if you still want/need your booking.
If you have a reliable 3G or LTE signal, you may also track where you are at any point during the ride a la Google Map.
Finally, you can send feedback if the cab driver happens to be rude or if you want to commend the service.
This entire process took only a minutes from our pick-up point in Ortigas yesterday which makes it perfect to use when you are in a hurry and you do not have the time nor the patience to wait for a taxi. It is also useful when you don't want to wait out in line when it is raining or when the heat is unbearable which seems to be the case most of the time. As far as apps go, this is definitely one of the most useful ones that I have downloaded.