I mainly wear bralettes as I refuse to wear bras with an underwire, those things are torture devices! I find myself wearing sports bras a lot lately because I've been on a 'get fit mission' for the last 6 months, trying to work off the weight I put on during college 😔
An advantage of being flat chested is that you can get away with going bra free if you're wearing a jumper or thicker T-shirt.