So this may sound like a dumb question, but is there a particular day of the week that suits App Store launches?
Before it was supposed to be Thursday, with today's App Store that updates more, I'm not really sure. I hope someone answers this.
Who knows anymore. Many factors are going to alter the results. If everyone thinks any day is the best day, then it won't be the best day anymore. Test and find out what works for you and you type of games.
If you want an Apple feature it is Thursday. And you have to write Apple 3-4 weeks ahead. If you don't aim at an Apple feature, well then it might be Friday. This way you are still in for the week-end and do not have the heavy competition of a Wednesday or a Thursday. Niche games might be completely different. But then, in the end it comes down anyway to the marketing and nothing else.