A new change to Pokemon Go will make playing while driving (or biking or riding a bus) much more difficult. Players over on Reddit noticed a change to the game's scan refresh rate, the tool the game uses to scan the surroundings for new Pokemon. When the game was first released in July, the scan refresh rate was once per second, but in recent weeks the game has scanned once every five seconds. Starting last night, the game now scans at a rate of once per every ten seconds.
So what does this mean for Pokemon Go players? We previously reported that Pokemon Go changed its coding so that Pokemon only stay visible for 70 meters. Coupled with the slower scan refresh rate, it will be much more difficult to see and catch Pokemon while traveling at speeds greater than 12.5 miles per hour. So if you're riding in a car or riding a bike, it's much more likely that the game won't detect Pokemon while driving OR they'll disappear from your screen before you have a chance to catch them.
If you primarily play Pokemon Go while walking, you probably won't notice a difference, but those that play on a bus or on a bike will probably see a sharp drop in the amount of Pokemon you'll encounter. It seems that the change was made primarily to curb playing Pokemon Go while driving, as there have been multiple reports of players crashing their cars while trying to catch a Pokemon. Some players have also complained that it hinders various tracking apps, which Pokemon Go was already trying to shut down anyways.