These are mostly Common Terns. The race wintering in SE Asia is S. h. longipennis in which the bill remains black year round. There is a smaller, paler Little Tern in the front. I believe the small shorebird directly in front is a Kentish Plover and the larger bird to the left is a Lesser Sand-Plover. Corrections always welcome.
Digiscoped with Panasonic DMC-LX5 | Nikon FieldScope III | 30XWA | hand-held (no adapter).