They trick and force you to pay extra fees
Do not fly with Indigo. Both their flights took off late and they play tricks to make you pay more for your flights. Their website is terrible; it does not let you pre-fill your passengers' details, so you must fill in a huuuge amount of information during booking and AGAIN during checkin. The website times out after about 15 minutes, so you must start all over again. If you do not check in within 3 hours of departure, they force you to pay extra but they do not tell you in advance - they say you can check in up to 60 minutes before your flight but they don't mention that you're forced to pay extra (or you cannot check-in). Deceitful practices.