Limited mobile internet can be instantly wasted if your iPhone does not have the 'Automatic download of updates' feature turned off. For those who did not know about the existence of such an option (which, by the way, is enabled by default), this instruction is intended. 1. Go to Settings
2. Select the iTunes Store section, App Store
3. Find the category 'Automatic downloads' and set the switch to OFF.
Now the updates will have to be done manually, but you will not 'fall' into uncontrolled traffic consumption. 4. If you are only interested in turning off mobile internet updates, you can only turn off 'Cellular Data'.
P.S. Disabling the “Automatic download” function is also a solution to the question of how to increase the operating time iPhone from one charge.