Manila airport transfer between terminals
In the past, when I have transferred between two terminals at Manila NAIA airport, I have had to go out to the curb and get the shuttle bus (which goes on the outside roads in heavy traffic) or get a taxi. This was not the case very recently. I arrived T3 and needed to transit to T2. There is a new transfer area that is well hidden, but very useful. You go there, show your itinerary, and go through x-ray, then you get on a van that stays INSIDE THE RAMP AREA of the airport all the way to T2. At T2, it pulls out of the secure area and drops you off at normal departures. This saves LOTS of time because there is no traffic.
To get to this new transit area, walk out of baggage claim and turn LEFT, then walk all the way to the end of the arrival hall, then turn left again and you will start to see signs saying "Transit for terminal 2". The person I spoke to said you can go to the same area in T3 to transit to T1, but the signs for T1 transit are not up yet. Just have your passport and printed itinerary. I saw some passengers get on the van to T1.