There are two main groups of Islands in India:

Lakshadweep
Lying 400 km west off the Malabar Coast – called Lakshadweep, comprising of approximately 36 coral islands and 12 atolls. Out of these 11 are inhabited and only three have facilities for tourists.
These are some of the finest, unexplored coral islands in the world, though facilities and infrastructure are not well developed.

Andaman and Nicobar Islands
Compared to Lakshadweep, the Andaman and Nicobars are much larger in scale. They span North-South in the Bay of Bengal, 700 – 800 km off the eastern coast.
The Andamans have some of the finest tropical forests in the world. Exotic species of flora and fauna and marine life abounds in the waters around these islands.
However, the scope of your visit is limited to a few islands around Port Blair. If you are willing to rough it out, you could go backpacking to the Nicobars (open only to Indians with a permit).

Diu
Though connected by a bridge, Diu is technically an island off the Gujarat coast. It has neither the splendour nor the natural beauty of Lakshadweep or the Andamans; however, it has a charm all its own and is rated highly by backpackers.

Travel Tips:
Many people ask us whether they should go to Lakshadweep or Andamans. We feel these are two distinctly different destinations, with little in common. The Andamans give you a feel which can be intimidating at times because of the scale - dense pristine forests, 30 metre high trees and long beaches. Some of the islands have gentle rolling hills, tiny rivulets and streams, ancient-tribes and volcanoes. The highest point in the Great Nicobar is 4000 feet above sea level.

On the other hand, the Lakshadweep islands are amongst the finest coral islands in the world. The clear aquamarine lagoons protected by a reef, make you feel cosy and safe from the wild ocean waves. The islands are comparatively tiny and flat with only coconut palms. The choice therefore is entirely yours!