Hidden Data Drains: Apps That Secretly Use Data in the Background While Traveling

https://wiki-spirit.win/index.php/Long-Term_Travel_Data_Needs:_Planning_Mobile_Internet_for_3-6_Month_Trips

You bought a 10 GB eSIM plan for your two-week trip. You've been careful — you stream only over Wi-Fi, you use maps offline, and you don't video call obsessively. So why is your data half-gone after five days? Background app activity