There have been a bunch of playground rumours circulating around Pokemon TCG Pocket. The big one is that if you find a slightly crooked pack in the carousel, you'll get Shiny cards. It's not true, but it turns out that the carousel itself might not have any impact whatsoever.
Yesterday, Reddit user Vurzey1 shared an interesting discovery. While their friend looked through the carousel, the Wonder Pick was already showing the cards he ended up pulling. That means the cards were determined before he ever chose a pack. In that case, what you open on the carousel doesn't matter.
One example is hardly enough to say for certain, so the community started testing it for themselves. YouTuber ninaisnoob found that if you close the app before choosing a pack from the carousel and then reopen it, you'll automatically be given the cards you would have unlocked. Several others, myself included, gave this a try and found the same.
Nintendo leaker Centro tried an even more damning method. They selected one of the three packs on the main menu, toggled Airplane Mode before the carousel, and found that "it will show you the cards, but won't be able to connect...