The best way to explore the island around is by private boat. It is affordable, and you can see places you can't visit by foot. This is excellent opportunity to go fishing on open sea or snorkel in outside reef.
Mas Wardi boat hire.Very friendly guy, unfortunately he does not speak English. He can take you places around Tidung and even around surrounding islands. If you are lucky you can spot and swim with dolphins!
T: +62 812 1811 5394
Google Plus Code (GPS): 6P686F2X+78