If you want to get even further away from civilization, not far from Koh Lipe Island in Thailand, there are two more islands where you can stay in fairly comfortable conditions while avoiding the hustle and bustle that grows on Koh Lipe every year. Both islands are very close to Koh Lipe, and you can easily get there by boat (see the islands on the Koh Lipe map). They are already part of the National Park, so you'll have to pay 200 baht for access, and 100 baht for children.
These islands are much larger than their little brother Koh Lipe, real giants in comparison. However, there is no tourist infrastructure on them whatsoever, except for the possibility of staying in bungalows or camping in a tent. There isn't even a basic store here. Adang has a cafe, but on Rawi, you'll have to bring everything with you.
Ko Adang and Ko Rawi are covered in dense jungle, lying on the slopes of hills, crisscrossed by a few trekking trails. Trekking through the jungle, visiting waterfalls, and climbing the hills for panoramic views of the ocean and neighboring islands are some of the most captivating activities here.
Along the perimeter of the islands are wonderful beaches that could easily be considered some of the most beautiful in Thailand. The sandy shore doesn't completely encircle the islands; most of the coastline here is rocky. But it's on these very best beaches that the few bungalows and campsites are located.
Another popular activity here is diving and snorkeling. There are no specially created dive sites like sunken ships here; mainly you can admire corals and the rich tropical underwater life. Objectively speaking, the conditions for diving here aren't the best.
Luckily, there are still no hotels on either Ko Adang or Ko Rawi. You can stay on Adang in bungalows in one of the several camps around the island from 600 baht per night. For the most adventurous and budget-conscious travelers, there's the option to camp in a tent for 30 baht per person if you have your own tent, or rent a tent here for 250 baht. On Rawi, there aren't even bungalows, and accommodation is only possible in a tent, and you must first get permission from the park office on Adang.
You can get to the islands by boat from Koh Lipe for 50-100 baht per person.