Several months ago, Pokemon Go instituted a "speed limit" to prevent players from playing the game while traveling above 30 miles per hour. The speed limit was enacted after multiple reports of car accidents caused by drivers distracted by Pokemon Go. Thanks to the speed limit, not only do Pokemon automatically despawn from Pokemon Go's map when traveling above the game's speed limit, the game also prevents players from obtaining items from PokeStops.
Earlier this week, a Redditor found a way to "bypass" the speed limit to spin PokeStops while driving. According to the Redditor, if a player opens and immediately closes their in-game journal, they will have a short window in which the game doesn't track the speed limit. Opening and closing the journal causes the game to "load," (indicated by a white PokeBall spinning in the corner of the screen) during which the player can spin PokeStops without worry.
The key to this trick is getting Pokemon Go to load, as this is when the game's speed limit stops working. Although there's other ways to get the game to "load" (in fact, the game occasionally loads at random), opening and closing the journal seems to be the only way to trigger it on command.
The only downside to this trick is that it does require a bit of timing, as it usually only takes a couple of seconds for the game to load. Although this trick will allow you to get PokeBalls and other items at any speed, we still recommend that players only try this trick while riding as a passenger and not while actually operating a vehicle.