Quick facts
Capital: Colombo – many people tend to skip it, but I think 1-2 days to visit the National Museum and also to take in the hustle and bustle is a perfect start.
Transport: Trains and tours/private car is the way to go, although the adventurous can consider renting a tuktuk and driving around the island!
Currency: Sri Lanka Rupees, cash is king! 1 USD = LKR 300, 5 HKD = LKR 193.11 (~200). It’s a closed currency so get your money exchanged on arrival at airport or at Ceylon Bank ATM.
Sim card: Tourist sim are available at most major telecom company and you can easily purchase them at the airport on arrival.
Handy apps: PickMe for taxi in city, Klook or GetYourGuide for tickets and activities
Language: local speaks Tamil or Sinhala, but most people in the tourism industry or big cities speak English.