Yes, i've been in April. Bali is as close as you can get to a 'year round' destination in Asia, with more rainfall in Jan & Feb. However, rains have come either early or late in most of the last 10 years. It's pleasantly warm without being overawing - 30-34 during the day. Nice breezes on the coast take the edges off. I would say April is a nice time to go. Chances you will see some rain whatever month you go. I was there last November and it rained 2 out of the 7 days I was there, but it fine.