Pokemon GO App Data Bug Is Back: Check Your Usage Now
It would appear that the data usage increase bug is back in Pokemon GO in the latest update to the app for BOTH iOS and Android. This wouldn't be a good thing if it were just one of the two platforms. Both platforms at once means Niantic needs to act on a fix as soon as possible.
Pokemon GO updated over the past several days to new iterations for both Android and iOS. If you're on an iPhone or using an iPad with Pokemon GO, you'll find update version 1.181.0 as the most recent version for the game (depending on when you read this article, of course). The latest Android version of the game appears to be 0.215.0, and both of these versions have given users a big of a hassle when it comes to data usage.
The spike in data use will likely appear in your smartphone's data use tracker starting on around the 25th or 26th of July, 2021, assuming you updated your Pokemon GO app on the day the latest release was first made available. If you're using an Android device, you'll find this version "forced" – meaning you'll not be able to play the game unless you update the app.
Per user BlueDragon147 on Reddit's The Silph Road, a spike in data use occurred after the update approximately 3 days ago. User Puzzleheaded_Ad550 reported a similar issue earlier today saying, "since yesterday the data Pokemon GO uses has almost tripled." User Falafelmeister92 (in the same thread) suggested that "in the past two weeks alone, I used more than 1GB. Previously, I would use around 500MB or less in a full month."
If you have this data spike, courtesy of Pokemon GO, you'll do well to stay on WiFi for a few days. This is not the sort of bug that sticks around for long – Niantic is very likely already working on a fix right this minute.
You may also want to use WiFi when opening the app, attempt to scroll through your whole Pokedex and check in on every different asset you can in the game first, to make sure you've downloaded all the data you can, then go back to mobile data. There's always a chance that the latest update simply re-booted a bunch of graphics, resulting in the need for a full game file download one time – but that'd mean it'd be fixed in quick order. We shall see!