We've all been there...its midway (or the end) through the month and all of your data is gone. Or, perhaps you have received an invoice with extra data charges. Many of us are left scratching our heads thinking "How did I go over?" or "I couldn't have possibly used THAT much data!"
The truth is, as technology advances Smartphones are using more data than ever before! Speaking from personal experience when I changed my device from an Iphone 4s to an Iphone 6+ I noticed my data usage increase substantially. I didn't feel I was doing anything different but clearly more data was being used. I knew then that I had to review my phone settings to find out where I could save on my data.
Here are some tips and tricks that will definitely help you save on your data 
Iphone Users:
Track how much IPhone data has been used (Since last reset, or since phone was first used)
ð Settings > Cellular
avoid higher data usage by disabling BACKGROUND APP REFRESH option in the iPhone.
ð Settings > General > Background App Refresh
In that screen you can select applications that you would prefer to be updated in the background. For example: Whatsapp. I would want Whatsapp to be on all the time so I receive my message promptly. But for an app like Instagram, some people may not need an instant update because they use it so frequently
Stop iCloud Drive using cellular data
ð Settings > iCloud > iCloud Drive > scroll down and disable Use Cellular Data
Deactivate Facebook AUTOPLAY
ð Open Facebook > More > Account Settings > Videos and Photos > disable Upload HD
ð Open Facebook > More > Account Settings > Videos and Photos > disable Smart Auto-Play and under Choose your Own Auto-Play Setting > select Use Wi-Fi Only
(Iphone) > tap Cellular Data Use > choose Default or Use Less Data
Disable LOCATION SERVICES
ð Settings > Privacy > Location Services >
In that screen you can select applications that you would prefer to “Always” allow location access or “Never” allow location access when LOCATION SERVICES is enabled
Disabling PHOTO STREAM and PHOTO SHARING
ð Settings > iCloud > Photos > disable iCloud Photo Library, My Photo Stream and iCloud Photo Sharing
Turn off Push Notifications
ð Settings > Notifications
You can easily stop any apps from pestering you with notifications, just scroll down the list, tap on those apps you don’t want to notify you, and toggle to switch beside: Allow Notification and switching it to OFF
Also by Turning off LTE on the Iphone. **Note- Data speed will be slower**
ð Settings > Cellular > disable Enable LTE
***Edited to add labels***
Another thing to make sure that you have turned off is WiFi Assist on iPhones
Android users are able to set up data warnings and a data block on their phone once it hits a certain threshhold - This can be done by going to Settings - Mobile Data.
