According to my knowledge, Naaf river(নাফ নদী) is the only one that is shared between Myanmar(মায়ানমার) and Bangladesh(বাংলাদেশ). The eastern coast of the river is Arakan(আরাকান) sate of Burma(বার্মা), and the western coast is Teknaf(টেকনাফ) of Bangladesh(বাংলাদেশ).
Naff Nodi(নাফ নদী) is originated from the Arakan Hills of Myanmar and after flowing as a trans-boundary river, and finally falls into the Bay of Bengal. The river is having 1-3 kilometer width between the two countries at some places and the depth of the river is having 130ft an average depth and highest depth is 400ft.
Being near to the ocean, the water of the river is salty. Also the water level has an ups and downs based on the high and low tide from the sea. Keeping similarity with the Bay of Bengal, the river has almost same color of the ocean.
While cruising through the river, I have found the sight of Myanmar side is more beautify compare to Bangladesh. May be the well known proverb "the other side of the river is always beautiful" is the reason.
Tourists of st martin's island are being carried by the ship over the river. During the cruising, you can see lot of boats were floating over the river. Boatmen from the both country use to catch fish on a regular basis.
Finally, the river has lot of Seagulls(গাংচিল) flying around. I have seen my first Seagull(গাংচিল) at Naaf River(নাফ নদী).